THE LIFE OF PASTEUR

“L’œuvre de Pasteur est admirable; elle montre son génie, mais il faut avoir vécu dans son intimité pour connaître toute la bonté de son cœur.”—Dr. Roux.

THE
LIFE OF PASTEUR

BY RENÉ VALLERY-RADOT
TRANSLATED FROM THE FRENCH BY
MRS. R. L. DEVONSHIRE
WITH AN INTRODUCTION BY
SIR WILLIAM OSLER, BART., M.D., F.R.S.
REGIUS PROFESSOR OF MEDICINE, OXFORD UNIVERSITY
NEW YORK
DOUBLEDAY, PAGE & COMPANY
1920

Printed in Great Britain by
Richard Clay & Sons, Limited,
BRUNSWICK ST., STAMFORD ST., S.E. 1,
AND BUNGAY, SUFFOLK.

INTRODUCTION

L’homme en ce siècle a pris une connaissance toute nouvelle des ressource de la nature et, par l’application de son intelligence il a commencé à les faire fructifier. Il a refait, par la géologie et la paléontologie, l’histoire de la terre, entraînée elle-même par la grande loi de l’évolution. Il connaît mieux, grâce à Pasteur surtout, les conditions d’existence de son propre organisme et peut entreprendre d’y combattre les causes de destruction.—Monod, L’Europe Contemporaine.

Whether to admire more the man or his method, the life or the work, I leave for the readers of this well-told story to decide. Among the researches that have made the name of Pasteur a household word in the civilised world, three are of the first importance—a knowledge of the true nature of the processes in fermentation—a knowledge of the chief maladies which have scourged man and animals—a knowledge of the measures by which either the body may be protected against these diseases, or the poison neutralised when once within the body.

I.

Our knowledge of disease has advanced in a curiously uniform way. The objective features, the symptoms, naturally first attracted attention. The Greek physicians, Hippocrates, Galen, and Aretaeus, gave excellent accounts of many diseases; for example, the forms of malaria. They knew, too, very well, their modes of termination, and the art of prognosis was studied carefully. But of the actual causes of disease they knew little or nothing, and any glimmerings of truth were obscured in a cloud of theory. The treatment was haphazard, partly the outcome of experience, partly based upon false theories of the cause of the disease. This may be said to have been the sort of knowledge possessed by the profession until men began to study the “seats and causes” of disease, and to search out the changes inside the body, corresponding to the outward symptoms and the external appearances. Morbid anatomy began to be studied, and in the hundred years from 1750 to 1850 such colossal strides were made that we knew well the post-mortem appearances of the more common diseases; the recognition of which was greatly helped by a study of the relation of the pathological appearances with the signs and symptoms. The 19th century may be said to have given us an extraordinarily full knowledge of the changes which disease produces in the solids and fluids of the body. Great advances, too, were made in the treatment of disease. We learned to trust Nature more and drugs less; we got rid (in part) of treatment by theory, and we ceased to have a drug for every symptom. But much treatment was, and still is, irrational, not based on a knowledge of the cause of the disease. In a blundering way many important advances were made, and even specifics were discovered—cinchona, for example, had cured malaria for a hundred and fifty years before Laveran found the cause. At the middle of the last century we did not know much more of the actual causes of the great scourges of the race, the plagues, the fevers and the pestilences, than did the Greeks. Here comes in Pasteur’s great work. Before him Egyptian darkness; with his advent a light that brightens more and more as the years give us ever fuller knowledge. The facts that fevers were catching, that epidemics spread, that infection could remain attached to particles of clothing, etc., all gave support to the view that the actual cause was something alive, a contagium vivum. It was really a very old view, the germs of which may be found in the Fathers, but which was first clearly expressed—so far as I know—by Frascastorius, a Veronese physician in the 16th century, who spoke of the seeds of contagion passing from one person to another; and he first drew a parallel between the processes of contagion and the fermentation of wine. This was more than one hundred years before Kircher, Leeuwenhoek, and others, began to use the microscope and to see animalculæ, etc., in water, and so gave a basis for the “infinitely little” view of the nature of disease germs. And it was a study of the processes of fermentation that led Pasteur to the sure ground on which we now stand. Starting as a pure chemist, and becoming interested in the science of crystallography, it was not until his life at Lille, a town with important brewing industries, that Pasteur became interested in the biological side of chemical problems. Many years before it had been noted by Cagniard-Latour that yeast was composed of cells capable of reproducing themselves by a sort of budding, and he made the keen suggestion that it was possibly through some effect of their vegetation that the sugar was transformed. But Liebig’s view everywhere prevailed that the ferment was an alterable, organic substance which exercised a catalytic force, transforming the sugar. It was in August, 1857, that Pasteur sent his famous paper on Lactic Acid Fermentation to the Lille Scientific Society; and in December of the same year he presented to the Academy of Sciences a paper on Alcoholic Fermentation, in which he concluded that the deduplication of sugar into alcohol and carbonic acid is correlevant to a phenomena of life. These studies had the signal effect of diverting the man from the course of his previous more strictly chemical studies. It is interesting to note how slowly these views dislocated the dominant theories of Liebig. More than ten years after their announcement I remember that we had in our chemical lectures the catalytic theory very fully presented.

Out of these researches arose a famous battle which kept Pasteur hard at work for four or five years—the struggle over spontaneous generation. It was an old warfare, but the microscope had revealed a new world, and the experiments on fermentation had lent great weight to the omne vivum ex ovo doctrine. The famous Italians, Redi and Spallanzani, had led the way in their experiments, and the latter had reached the conclusion that there is no vegetable and no animal that has not its own germ. But heterogenesis became the burning question, and Pouchet in France, and Bastian in England, led the opposition to Pasteur. The many famous experiments carried conviction to the minds of scientific men, and destroyed for ever the old belief in spontaneous generation. All along the analogy between disease and fermentation must have been in Pasteur’s mind; and then came the suggestion: “What would be most desirable would be to push those studies far enough to prepare the road for a serious research into the origin of various diseases.” If the changes in lactic, alcohol and butyric fermentations are due to minute living organisms, why should not the same tiny creatures make the changes which occur in the body in the putrid and suppurative diseases. With an accurate training as a chemist, having been diverted in his studies upon fermentation into the realm of biology, and nourishing a strong conviction of the identity between putrefactive changes of the body and fermentation, Pasteur was well prepared to undertake investigations, which had hitherto been confined to physicians alone.

The first outcome of the researches of Pasteur upon fermentation and spontaneous generation represents a transformation in the practice of surgery, which, it is not too much to say, has been one of the greatest boons ever conferred upon humanity. It had long been recognised that now and again a wound healed without the formation of pus, that is without suppuration, but both spontaneous and operative wounds were almost invariably associated with that change; and, moreover, they frequently became putrid, as it was then called—infected, as we should say; the general system became involved, and the patient died of blood poisoning. So common was this, particularly in old, ill-equipped hospitals, that many surgeons feared to operate, and the general mortality in all surgical cases was very high. Believing that from outside the germs came which caused the decomposition of wounds, just as from the atmosphere the sugar solution got the germs which caused the fermentation, a young surgeon at Glasgow, Joseph Lister, applied the principles of Pasteur’s experiments to their treatment. It may be well here to quote from Lister’s original paper in the Lancet, 1867:—“Turning now to the question how the atmosphere produces decomposition of organic substances, we find that a flood of light has been thrown upon this most important subject by the philosophic researches of M. Pasteur, who has demonstrated by thoroughly convincing evidence that it is not to its oxygen or to any of its gaseous constituents that the air owes this property, but to minute particles suspended in it, which are the germs of various low forms of life, long since revealed by the microscope, and regarded as merely accidental concomitants of putrescence, but now shown by Pasteur to be its essential cause, resolving the complex organic compounds into substances of simpler chemical constitution, just as the yeast plant converts sugar into alcohol and carbonic acid.” From these beginnings modern surgery took its rise, and the whole subject of wound infection, not only in relation to surgical diseases, but to child-bed fever, forms now one of the most brilliant chapters in the history of Preventive Medicine.

II.

Pasteur was early impressed with the analogies between fermentation and putrefaction and the infectious diseases, and in 1863 he assured the French Emperor that his ambition was “to arrive at the knowledge of the causes of putrid and contagious diseases.” After a study upon the diseases of wines, which has had most important practical bearings, an opportunity came of the very first importance, which not only changed the whole course of his career, but had great influence in the development of medical science. A disease of the silkworm had, for some years, ruined one of the most important industries of France, and in 1865 the Government asked Pasteur to give up the laboratory work and teaching, and to devote his whole energies to the task of investigating it. The story of the brilliant success which followed years of application to the problem will be read with deep interest by every student of science. It was the first of his victories in the application of the experimental methods of a trained chemist to the problems of biology, and it placed his name high in the group of the most illustrious benefactors of practical industries.

The national tragedy of 1870-2 nearly killed Pasteur. He had a terrible pilgrimage to make in search of his son, a sergeant in Bourbaki’s force. “The retreat from Moscow cannot have been worse than this,” said the savant. In October, 1868, he had had a stroke of paralysis, from which he recovered in a most exceptional way, as it seemed to have diminished neither his enthusiasm nor his energy. In a series of studies on the diseases of beer, and on the mode of production of vinegar, he became more and more convinced that these studies on fermentation had given him the key to the nature of the infectious diseases. It is a remarkable fact that the distinguished English philosopher of the seventeenth century, the man who more than any one else of his century appreciated the importance of the experimental method, Robert Boyle, had said that he who could discover the nature of ferments and fermentation, would be more capable than anyone else of explaining the nature of certain diseases. The studies on spontaneous generation, and Lister’s application of the germ theory to the treatment of wounds, had aroused the greatest interest in the medical world, and Villemin, in a series of most brilliant experiments, had demonstrated the infectivity of tuberculosis. An extraordinary opportunity now offered for the study of a widespread epidemic disease, known as anthrax, which in many parts of France killed from 25 to 30 per cent. of the sheep and cattle, and which in parts of Europe had been pandemic, attacking both man and beast. As far back as 1838 minute rods had been noted in the blood of animals which had died from the disease; and in 1863 Devaine thought that these little bodies, which he called bacteridia, were the cause of the disease. In 1876 a young German district physician, Robert Koch, began a career, which in interest and importance rivals that of the subject of this memoir. Koch confirmed in every point the old researches of Devaine; but he did much more, and for the first time isolated the organism in pure culture outside the body, grew successive generations, showed the remarkable spore formation, and produced the disease artificially in animals by inoculating with the cultures. Pasteur confirmed these results, and in the face of extraordinary opposition succeeded in convincing his opponents. Out of this study came a still more important discovery, namely, that it was possible so to attenuate or weaken the virus or poison that the animal could be inoculated, and have a slight attack, recover, and be protected against the disease. More than eighty years had passed since, on May 14th, 1796, Jenner, with a small bit of virus taken from a cow-pox on the hand of the milkmaid, Sarah Newlme, had vaccinated a child, and thus proved that a slight attack of one disease would protect the body from disease of a similar character. It was an occasion famous in the history of medicine, when, in the spring of 1881, at Melun, at the farmyard of Pouilly le Fort, the final test case was determined, and the flock of vaccinated sheep remained well, while every one of the unvaccinated, inoculated from the same material, had died. It was indeed a great triumph.

The studies on chicken cholera, yellow fever, and on swine plague helped to further the general acceptance of the germ theory. I well remember at the great meeting of the International Congress in 1881, the splendid reception accorded to the distinguished Frenchman, who divided with Virchow the honours of the meeting. Finally came the work upon one of the most dreaded of all diseases—hydrophobia, an infection of a most remarkable character, the germ of which remains undiscovered. The practical results of Pasteur’s researches have given us a prophylactic treatment of great efficacy. Before its introduction the only means of preventing the development of the disease was a thorough cauterisation of the disease wound within half an hour after its infliction. Pasteur showed that animals could be made immune to the poison, and devised a method by which the infection conveyed by the bite could be neutralised. Pasteur Institutes for the treatment of hydrophobia have been established in different countries, and where the disease is widely prevalent have been of the greatest benefit. Except at the London Congress, the only occasion on which I saw the great master was in 1891 or 1892, when he demonstrated at the Institute to a group of us the technique of the procedure, and then superintended the inoculations of the day. A large number of persons are treated in the course of the year; a good many, of course, have not been bitten by mad dogs; but a very careful classification is made:—

(a) Includes persons bitten by dogs proved experimentally to have been mad.

(b) Persons bitten by dogs declared to be mad by competent veterinary surgeons.

(c) All other cases.

The mortality even in Class A is very slight, though many patients are not brought until late. Incidentally it may be remarked the lesson of this country in its treatment of hydrophobia is one of the most important ever presented in connection with an infectious disease. There are no Pasteur Institutes; there are no cases. Why? The simple muzzling order has prevented the transmission of the disease from dog to dog, and once exterminated in the dog, the possibility of the infection in man had gone. In 1888 the crowning work of Pasteur’s life was the establishment of an Institute to serve as a centre of study on contagious disease, and a dispensary for the treatment of hydrophobia, which is to-day the most important single centre of research in the world. The closing years of his life were full of interest in the work of his colleagues and assistants, and he had the great satisfaction of participating, with his assistant Roux, in another great victory over the dread scourge, diphtheria. Before his death in 1895 he had seen his work prosper in a way never before granted to any great discoverer. To no one man has it ever been given to accomplish work of such great importance for the well-being of humanity. As Paul Bert expressed it in the report to the French Government, Pasteur’s work constitutes three great discoveries, which may be thus formulated. 1. Each fermentation is produced by the development of a special microbe.

2. Each infectious disease is produced by the development within the organism of a special microbe.

3. The microbe of an infectious disease culture, under certain detrimental condition is attenuated in its pathogenic activity; from a virus it has become a vaccine.

In an address delivered in Edinburgh by Sir James Simpson in 1853, in which he extolled the recent advancement of physic, occur these words:—“I do not believe, that, at the present moment, any individual in the profession, who, in surgery or in midwifery, could point out some means of curing—or some prophylactic means of averting by antecedent treatment—the liability to these analogous or identical diseases—viz., surgical or puerperal fever—such a fortunate individual would, I say, make, in relation to surgery and midwifery, a greater and more important discovery than could possibly be attained by any other subject of investigation. Nor does such a result seem hopelessly unattainable.” Little did he think that the fulfilment of these words was in the possession of a young Englishman who had just gone to Edinburgh as an assistant to his colleague, Professor Syme. Lister’s recognition of the importance of Pasteur’s studies led to the fulfilment within this generation of the pious hope expressed by Simpson. In Institutions and Hospitals surgical infection and puerperal fevers are things of the past, and for this achievement if for nothing else, the names of Louis Pasteur and Joseph Lister will go down to posterity among those of the greatest benefactors of humanity.

III.

In his growth the man kept pace with the scientist—heart and head held even sway in his life. To many whose estimate of French character is gained from “yellow” literature this story will reveal the true side of a great people, in whom filial piety, brotherly solicitude, generosity, and self-sacrifice are combined with a rare devotion to country. Was there ever a more charming picture than that of the family at Dôle! Napoleon’s old sergeant, Joseph Pasteur, is almost as interesting a character as his illustrious son; and we follow the joys and sorrows of the home with unflagging attention. Rarely has a great man been able to pay such a tribute to his father as that paid by Pasteur:—“For thirty years I have been his constant care, I owe everything to him.”

This is a biography for young men of science, and for others who wish to learn what science has done, and may do, for humanity. From it may be gleaned three lessons.

The value of method, of technique, in the hands of a great master has never been better illustrated. Just as Harvey, searching out Nature by way of experiment, opened the way for a study of the functions of the body in health, so did Pasteur, bringing to the problems of biology the same great organon, shed a light upon processes the nature of which had defied the analysis of the keenest minds. From Dumas’s letter to Pasteur, quoted in Chapter VI., a paragraph may be given in illustration:—“The art of observation and that of experiment are very distinct. In the first case, the fact may either proceed from logical reasons or be mere good fortune; it is sufficient to have some penetration and the sense of truth in order to profit by it. But the art of experimentation leads from the first to the last link of the chain, without hesitation and without a blank, making successive use of Reason, which suggests an alternative, and of Experience, which decides on it, until, starting from a faint glimmer, the full blaze of light is reached.” Pasteur had the good fortune to begin with chemistry, and with the science of crystallography, which demanded extraordinary accuracy, and developed that patient persistence so characteristic of all his researches.

In the life of a young man the most essential thing for happiness is the gift of friendship. And here is the second great lesson. As a Frenchman, Pasteur had the devotion that marks the students of that nation to their masters, living and dead. Not the least interesting parts of this work are the glimpses we get of the great teachers with whom he came in contact. What a model of a scientific man is shown in the character of Biot, so keenly alive to the interests of his young friend, whose brilliant career he followed with the devotion of a second father. One of the most touching incidents recorded in the book relates to Pasteur’s election to the Academy of Sciences:—“The next morning when the gates of the Montparnasse cemetery were opened, a woman walked towards Biot’s grave with her hands full of flowers. It was Mme. Pasteur who was bringing them to him ... who had loved Pasteur with so deep an affection.” Pasteur looked upon the cult of great men as a great principle in national education. As he said to the students of the University of Edinburgh:—“Worship great men”;[1] and this reverence for the illustrious dead was a dominant element in his character, though the doctrines of Positivism seemed never to have had any attraction for him. A dark shadow in the scientific life is often thrown by a spirit of jealousy, and the habit of suspicious, carping criticism. The hall-mark of a small mind, this spirit should never be allowed to influence our judgment of a man’s work, and to young men a splendid example is here offered of a man devoted to his friends, just and generous to his rivals, and patient under many trying contradictions and vexatious oppositions.

And the last great lesson is humility before the unsolved problems of the Universe. Any convictions that might be a comfort in the sufferings of human life had his respectful sympathy. His own creed was beautifully expressed in his eulogy upon Littré:—“He who proclaims the existence of the Infinite, and none can avoid it—accumulates in that affirmation more of the supernatural than is to be found in all the miracles of all the religions; for the notion of the Infinite presents that double character that it forces itself upon us and yet is incomprehensible. When this notion seizes upon our understanding, we can but kneel.... I see everywhere the inevitable expression of the Infinite in the world; through it, the supernatural is at the bottom of every heart. The idea of God is a form of the idea of the Infinite. As long as the mystery of the Infinite weighs on human thought, temples will be erected for the worship of the Infinite, whether God is called Brahma, Allah, Jehovah, or Jesus; and on the pavement of those temples, men will be seen kneeling, prostrated, annihilated in the thought of the Infinite.” And modern Pantheism has never had a greater disciple, whose life and work set forth the devotion to an ideal—that service to humanity is service to God:—“Blessed is he who carries within himself a God, an ideal, and who obeys it: ideal of art, ideal of science, ideal of the gospel virtues, therein lie the springs of great thoughts and great actions; they all reflect light from the Infinite.”

The future belongs to Science. More and more she will control the destinies of the nations. Already she has them in her crucible and on her balances. In her new mission to humanity she preaches a new gospel. In the nineteenth century renaissance she has had great apostles, Darwin, for example, whose gifts of heart and head were in equal measure, but after re-reading for the third or fourth time the Life of Louis Pasteur, I am of the opinion, expressed recently by the anonymous writer of a beautiful tribute in the Spectator, “that he was the most perfect man who has ever entered the Kingdom of Science.”

William Osler.

CONTENTS

CHAPTER I
1822—1843

The origin of even the humblest families can be traced back by persevering search through the ancient parochial registers. Thus the name of Pasteur is to be found written at the beginning of the seventeenth century in the old registers of the Priory of Mouthe, in the province of Franche Comté. The Pasteurs were tillers of the soil, and originally formed a sort of tribe in the small village of Reculfoz, dependent on the Priory, but they gradually dispersed over the country.

The registers of Mièges, near Nozeroy, contain an entry of the marriage of Denis Pasteur and Jeanne David, dated February 9, 1682. This Denis, after whom the line of Pasteur’s ancestors follows in an unbroken record, lived in the village of Plénisette, where his eldest son Claude was born in 1683. Denis afterward sojourned for some time in the village of Douay, and ultimately forsaking the valley of Mièges came to Lemuy, where he worked as a miller for Claude François Count of Udressier, a noble descendant of a secretary of the Emperor Charles V.

Lemuy is surrounded by wide plains affording pasture for herds of oxen. In the distance the pine trees of the forest of Joux stand close together, like the ranks of an immense army, their dark masses deepening the azure of the horizon. It was in those widespreading open lands that Pasteur’s ancestors lived. Near the church, overshadowed by old beech and lime trees, a tombstone is to be found overgrown with grass. Some members of the family lie under that slab naïvely inscribed: “Here lie, each by the side of the others....”

In 1716, in the mill at Lemuy, ruins of which still exist, the marriage contract of Claude Pasteur was drawn up and signed in the presence of Henry Girod, Royal notary of Salins. The father and mother declared themselves unable to write, but we have the signatures of the affianced couple, Claude Pasteur and Jeanne Belle, affixed to the record of the quaint betrothal oath of the time. This Claude was in his turn a miller at Lemuy, though at his death in 1746 he is only mentioned as a labourer in the parish register. He had eight children, the youngest, whose name was Claude Etienne, and who was born in the village of Supt, a few kilometres from Lemuy, being Louis Pasteur’s great-grandfather.

What ambition, what love of adventures induced him to leave the Jura plains to come down to Salins? A desire for independence in the literal sense of the word. According to the custom then still in force in Franche Comté (in contradiction to the name of that province, as Voltaire truly remarks), there were yet some serfs, that is to say, people legally incapable of disposing of their goods or of their persons. They were part of the possessions of a nobleman or of the lands of a convent or monastery. Denis Pasteur and his son had been serfs of the Counts of Udressier. Claude Etienne desired to be freed and succeeded in achieving this at the age of thirty, as is proved by a deed, dated March 20, 1763, drawn up in the presence of the Royal notary, Claude Jarry. Messire Philippe-Marie-François, Count of Udressier, Lord of Ecleux, Cramans, Lemuy and other places, consented “by special grace” to free Claude Etienne Pasteur, a tanner, of Salins, his serf. The deed stipulated that Claude Etienne and his unborn posterity should henceforth be enfranchised from the stain of mortmain. Four gold pieces of twenty-four livres were paid then and there in the mansion of the Count of Udressier by the said Pasteur.

The following year, he married Françoise Lambert. After setting up together a small tannery in the Faubourg Champtave they enjoyed the fairy tale ideal of happiness: they had ten children. The third, Jean Henri, through whom this genealogy continues, was born in 1769. On June 25, 1779, letters giving Claude Etienne Pasteur the freedom of the city of Salins were delivered to him by the Town Council.

Jean Henri Pasteur, in his twentieth year, went to Besançon to seek his fortune as a tanner, but was not successful. His wife, Gabrielle Jourdan, died at the age of twenty, and he married again, but himself died at twenty-seven, leaving one little son by his first marriage, Jean Joseph Pasteur, born March 16, 1791. This child, who was to be Louis Pasteur’s father, was taken charge of by his grandmother at Salins; later on, his father’s sisters, one married to a wood merchant named Chamecin, and the other to Philibert Bourgeois, Chamecin’s partner, adopted the orphan. He was carefully brought up, but without much learning; it was considered sufficient in those days to be able to read the Emperor’s bulletins; the rest did not seem to matter very much. Besides, Jean Joseph had to earn his living at the tanner’s trade, which had been his father’s and his grandfather’s before him.

Jean Joseph was drawn as a conscript in 1811, and went through the Peninsular War in 1812 and 1813. He belonged to the 3rd Regiment of the Line, whose mission was to pursue in the northern Spanish provinces the guerillas of the famous Espoz y Mina. A legend grew round this wonderful man; he was said to make his own gunpowder in the bleak mountain passes; his innumerable partisans were supplied with arms and ammunition by the English cruisers. He dragged women and old men after him, and little children acted as his scouts. Once or twice however, in May, 1812, the terrible Mina was very nearly caught; but in July he was again as powerful as ever. The French had to organize mobile columns to again occupy the coast and establish communications with France. There was some serious fighting. Mina and his followers were incessantly harassing the small French contingent of the 3rd and 4th Regiments, which were almost alone. “How many traits of bravery,” writes Tissot, “will remain unknown which on a larger field would have been rewarded and honoured!”

The records of the 3rd Regiment allow us to follow step by step this valiant little troop, and among the rank and file, doing his duty steadily through terrible hardships, that private soldier (a corporal in July, 1812, and a sergeant in October, 1813) whose name was Pasteur. The battalion returned to France at the end of January, 1814. It formed a part of that Leval division which, numbering barely 8,000 men, had to fight at Bar-sur-Aube against an army of 40,000 enemies. The 3rd Regiment was called “brave amongst the brave.” “If Napoleon had had none but such soldiers,” writes Thiers in his History of the Consulate and the Empire, “the result of that great struggle would certainly have been different.” The Emperor, touched by so much courage, distributed crosses among the men. Pasteur was made a sergeant-major on March 10, 1814, and received, two days later, the cross of the Legion of Honour.

At the battle of Arcis-sur-Aube (March 21) the Leval division had again to stand against 50,000 men—Russians, Austrians, Bavarians, and Wurtembergers. Pasteur’s battalion, the 1st of the 3rd Regiment, came back to St. Dizier and went on by forced marches to Fontainebleau, where Napoleon had concentrated all his forces, arriving on April 4. The battalion was now reduced to eight officers and 276 men. The next day, at twelve o’clock, the Leval division and the remnant of the 7th corps were gathered in the yard of the Cheval Blanc Inn and were reviewed by Napoleon. The attitude of these soldiers, who had heroically fought in Spain and in France, and who were still offering their passionate devotion, gave him a few moments’ illusion. Their enthusiasm and acclamations contrasted with the coldness, the reserve, the almost insubordinations of Generals like Ney, Lefebvre, Oudinot and MacDonald, who had just declared that to march on Paris would be folly.

Marmont’s defection hastened events; the Emperor, seeing himself forsaken, abdicated. Jean Joseph Pasteur had not, like Captain Coignet, the sad privilege of witnessing the Emperor’s farewell, his battalion having been sent into the department of Eure on April 9. On April 23 the white cockade replaced the tricolour.

On May 12, 1814, a royal order gave to the 3rd line Regiment the name of “Régiment Dauphin”; it was reorganized at Douai, where Sergeant-major Pasteur received his discharge from the service. He returned to Besançon with grief and anger in his heart: for him, as for many others risen from the people, Napoleon was a demi-god. Lists of victories, principles of equality, new ideas scattered throughout the nations, had followed each other in dazzling visions. It was a cruel trial for half-pay officers, old sergeants, grenadiers, peasant soldiers, to come down from this imperial epic to every-day monotony, police supervision, and the anxieties of poverty; their wounded patriotism was embittered by feelings of personal humiliation. Jean Joseph resigned himself to his fate and went back to his former trade. The return from Elba was a ray of joy and hope in his obscure life, only to be followed by renewed darkness.

He was living in the Faubourg Champtave a solitary life in accordance with his tastes and character when this solitude was interrupted for an instant. The Mayor of Salins, a knight of Malta and an ardent royalist, ordered all the late soldiers of Napoleon, the “brigands de la Loire” as they were now called, to bring their sabres to the Mairie. Joseph Pasteur reluctantly obeyed; but when he heard that these glorious weapons were destined to police service, and would be used by police agents, further submission seemed to him intolerable. He recognized his own sergeant-major’s sabre, which had just been given to an agent, and, springing upon the man, wrested the sword from him. Great excitement ensued—a mixture of indignation, irritation and repressed enthusiasm; the numerous Bonapartists in the town began to gather together. An Austrian regiment was at that time still garrisoned in the town. The Mayor appealed to the colonel, asking him to repress this disobedience; but the Austrian officer refused to interfere, declaring that he both understood and approved the military feelings which actuated the ex-sergeant-major. Pasteur was allowed to keep his sword, and returned home accompanied by sympathizers who were perhaps more noisily enthusiastic than he could have wished.

Having peacefully resumed his work he made the acquaintance of a neighbouring family of gardeners, whose garden faced his tannery on the other bank of the “Furieuse,” a river rarely deserving its name. From the steps leading to the water Jean Joseph Pasteur often used to watch a young girl working in the garden at early dawn. She soon perceived that the “old soldier”—very young still; he was but twenty-five years old—was interested in her every movement. Her name was Jeanne Etiennette Roqui.

Her parents, natives of Marnoz, a village about four kilometres from Salins, belonged to one of the most ancient plebeian families of the country. The Salins archives mention a Roqui working in vineyards as far back as 1555, and in 1659 there were Roqui lampmakers and plumbers. The members of this family were in general so much attached to each other that “to love like the Roqui” had become proverbial; their wills and testaments mentioned legacies or gifts from brother to brother, uncle to nephew. In 1816 the father and mother of Jeanne Etiennette were living very quietly in the old Salins faubourg. Their daughter was modest, intelligent and kind; Jean Joseph Pasteur asked for her hand in marriage. They seemed made for each other; the difference in their natures only strengthened their mutual affection: he was reserved, almost secretive, with a slow and careful mind apparently absorbed in his own inner life; she was very active, full of imagination, and ready enthusiasm.

The young couple migrated to Dôle and settled down in the Rue des Tanneurs. Their first child only lived a few months; in 1818 a little daughter came. Four years later in a small room of their humble home, on Friday, December 27, 1822, at 2 a.m., Louis Pasteur was born.

Two daughters were born later—one at Dôle and the other at Marnoz, in the house of the Roqui. Jean Joseph Pasteur’s mother-in-law, now a widow, considering that her great age no longer allowed her to administer her fortune, had divided all she possessed between her son Jean Claude Roqui, a landed proprietor at Marnoz, and Jeanne Etiennette her daughter.

Thus called away from Dôle by family interests, Jean Joseph Pasteur came to live at Marnoz. The place was not very favourable to his trade, though a neighbouring brook rendered the establishment of a tannery possible. The house, though many times altered, still bears the name of “Maison Pasteur.” On one of the inner doors the veteran, who had a taste for painting, had depicted a soldier in an old uniform now become a peasant and tilling the soil. This figure stands against a background of grey sky and distant hills; leaning on his spade the man suspends his labours and dreams of past glories. It is easy to criticize the faults in the painting, but the sentimental allegory is full of feeling.

Louis Pasteur’s earliest recollections dated from that time; he could remember running joyously along the Aiglepierre road. The Pasteur family did not remain long at Marnoz. A tannery was to let in the neighbourhood by the town of Arbois, near the bridge which crosses the Cuisance, and only a few kilometres from the source of the river. The house, behind its modest frontage, presented the advantage of a yard where pits had been dug for the preparation of the skins. Joseph Pasteur took this little house and settled there with his wife and children.

Louis Pasteur was sent at first to the “Ecole Primaire” attached to the college of Arbois. Mutual teaching was then the fashion; scholars were divided into groups: one child taught the rudiments of reading to others, who then spelt aloud in a sort of sing-song. The master, M. Renaud, went from group to group designating the monitors. Louis soon desired to possess this title, perhaps all the more so because he was the smallest scholar. But those who would decorate the early years of Louis Pasteur with wonderful legends would be disappointed: when a little later he attended the daily classes at the Arbois college he belonged merely to the category of good average pupils. He took several prizes without much difficulty; he rather liked buying new lesson books, on the first page of which he proudly wrote his name. His father, who wished to instruct himself as well as to help his son, helped him with his home preparation. During holidays, the boy enjoyed his liberty. Some of his schoolfellows—Vercel, Charrière, Guillemin, Coulon—called for him to come out with them and he followed them with pleasure. He delighted in fishing parties on the Cuisance, and much admired the net throwing of his comrade Jules Vercel. But he avoided bird trapping; the sight of a wounded lark was painful to him.

The doors of Louis Pasteur’s home were not usually open except to his schoolboy friends, who, when they did not fetch him away, used to come and play in the tannery yard with remnants of bark, stray bits of iron, etc. Joseph Pasteur, though not considered a proud man, did not easily make friends. His language and manners were not those of a retired sergeant; he never spoke of his campaigns and never entered a café. On Sundays, wearing a military-looking frock coat, spotlessly clean and adorned with the showy ribbon of the Legion of Honour (worn very large at that time), he invariably walked out towards the road from Arbois to Besançon. This road passes between vine-planted hills. On the left, on a wooded height above the wide plain towards Dôle, the ruins of the Vadans tower invest the whole landscape with a lingering glamour of heroic times. In these solitary meditations, he dwelt more anxiously on the future than on present difficulties, the latter being of little account in this hard-working family. What would become of this son of his, conscientious and studious, but, though already thirteen years old, with no apparent preference for anything but drawing? The epithet of artist given to Louis Pasteur by his Arboisian friends only half pleased the paternal vanity. And yet it is impossible not to be struck by the realism of his first original effort, a very bold pastel drawing. This pastel represents Louis’ mother, one morning that she was going to market, with a white cap and a blue and green tartan shawl. Her son insisted on painting her just as she was. The portrait is full of sincerity and not unlike the work of a conscientious pre-Raphaelite. The powerful face is illumined by a pair of clear straightforward eyes.

Though they did not entertain mere acquaintances, the husband and wife were happy to receive those who seemed to them worthy of affection or esteem by reason of some superiority of the mind or of the heart. In this way they formed a friendship with an old army doctor then practising in the Arbois hospital, Dr. Dumont, a man who studied for the sake of learning and who did a great deal of good while avoiding popularity.

Another familiar friend was a philosopher named Bousson de Mairet. An indefatigable reader, he never went out without a book or pamphlet in his pocket. He spent his life in compiling from isolated facts annals in which the characteristics of the Francs-Comtois, and especially the Arboisians, were reproduced in detail, with labour worthy of a Benedictine monk. He often came to spend a quiet evening with the Pasteur family, who used to question him and to listen to his interesting records of that strange Arboisian race, difficult to understand, presenting as it does a mixture of heroic courage and that slightly ironical good humour which Parisians and Southerners mistake for naïveness. Arboisians never distrust themselves, but are sceptical where others are concerned. They are proud of their local history, and even of their rodomontades.

For instance, on August 4, 1830, they sent an address to the Parisians to express their indignation against the “Ordonnances”[2] and to assure them that all the available population of Arbois was ready to fly to the assistance of Paris. In April, 1834, a lawyer’s clerk, passing one evening through Arbois by the coach, announced to a few gardes nationaux who were standing about that the Republic was proclaimed at Lyons. Arbois immediately rose in arms; the insurgents armed themselves with guns from the Hôtel de Ville. Louis Pasteur watched the arrival from Besançon of 200 grenadiers, four squadrons of light cavalry, and a small battery of artillery sent to reduce the rebels. The sous-préfet of Poligny having asked the rioters who were their leaders, they answered with one voice, “We are all leaders.” A few days later the great, the good news was published in all the newspapers: “Arbois, Lyons, and Paris are pacified.” The Arboisians called their neighbours “the Braggarts of Salins,” probably with the ingenious intention of turning such a well-deserved accusation from themselves.

Louis Pasteur, whose mind already had a serious bent, preferred to these recent anecdotes such historical records as that of the siege of Arbois under Henry IV, when the Arboisians held out for three whole days against a besieging army of 25,000 men. His childish imagination, after being worked upon by these stories of local patriotism, eagerly seized upon ideals of a higher patriotism, and fed upon the glory of the French people as represented by the conquests of the Empire.

He watched his parents, day by day working under dire necessity and ennobling their weary task by considering their children’s education almost as essential as their daily bread; and, as in all things the father and mother took an interest in noble motives and principles, their material life was lightened and illumined by their moral life.

One more friend, the headmaster of Arbois college, M. Romanet, exerted a decisive influence on Louis Pasteur’s career. This master, who was constantly trying to elevate the mind and heart of his pupils, inspired Louis with great admiration as well as with respect and gratitude. Romanet considered that whilst instruction doubled a man’s value, education, in the highest sense of the word, increased it tenfold. He was the first to discover in Louis Pasteur the hidden spark that had not yet revealed itself by any brilliant success in the hardworking schoolboy. Louis’ mind worked so carefully that he was considered slow; he never affirmed anything of which he was not absolutely sure; but with all his strength and caution he also had vivid imaginative faculties.

Romanet, during their strolls round the college playground, took pleasure in awakening with an educator’s interest the leading qualities of this young nature—circumspection and enthusiasm. The boy, who had been sitting over his desk with all-absorbing attention, now listened with sparkling eyes to the kind teacher talking to him of his future and opening to him the prospect of the great Ecole Normale.[3]

An officer of the Paris municipal guard, Captain Barbier, who always came to Arbois when on leave, offered to look after Louis Pasteur if he were sent to Paris. But Joseph Pasteur—in spite of all—hesitated to send his son, not yet sixteen years old, a hundred leagues away from home. Would it not be wiser to let him go to Besançon college and come back to Arbois college as professor? What could be more desirable than such a position? Surely Paris and the Ecole Normale were quite unnecessary! The question of money also had to be considered.

“That need not trouble you,” said Captain Barbier. “In the Latin Quarter, Impasse des Feuillantines, there is a preparatory school, of which the headmaster, M. Barbet, is a Franc-Comtois. He will do for your son what he has done for many boys from his own country—that is, take him at reduced school fees.”

Joseph Pasteur at last allowed himself to be persuaded, and Louis’ departure was fixed for the end of October, 1838. He was not going alone: Jules Vercel, his dear school friend, was also going to Paris to work for his “baccalauréat.”[4] This youth had a most happy temperament: unambitious, satisfied with each day’s work as it came, he took pride and pleasure in the success of others, and especially in that of “Louis,” as he then and always fraternally called his friend. The two boys’ friendship went some way to alleviate the natural anxieties felt by both families. The slowness and difficulty of travelling in those days gave to farewells a sort of solemn sadness; they were repeated twenty times whilst the horses were being harnessed and the luggage hoisted on to the coach in the large courtyard of the “Hôtel de la Poste.” On that bleak October morning, amidst a shower of rain and sleet, the two lads had to sit under the tarpaulin behind the driver; there were no seats left inside or under the hood. In spite of Vercel’s habit of seeing the right side of things and his joy in thinking that in forty-eight hours he, the country boy, would see the wonders of Paris—in spite of Pasteur’s brave resolve to make the most of his unexpected opportunities of study, of the now possible entrance into the “Ecole Normale”—both looked with heavy hearts at the familiar scene they were leaving behind them—their homes, the square tower of Arbois church, the heights of the Ermitage in the grey distance.

Every native of Jura, though he affects to feel nothing of the kind, has, at the bottom of his heart, a strong feeling of attachment for the corner of the world where he has spent his childhood; as soon as he forsakes his native soil his thoughts return to it with a painful and persistent charm. The two boys did not take much interest in the towns where the coach stopped to change horses, Dôle, Dijon, Auxerre, Joigny, Sens, Fontainebleau, etc.

When Louis Pasteur reached Paris he did not feel like Balzac’s student hero, confidently defying the great city. In spite of the strong will already visible in his pensive features, his grief was too deep to be reasoned away. No one at first suspected this; he was a reserved youth, with none of the desire to talk which leads weak natures to ease their sorrows by pouring them out; but, when all was quiet in the Impasse des Feuillantines and his sleeping comrades could not break in upon his regrets, he would lie awake for hours thinking of his home and repeating the mournful line—

How endless unto watchful anguish
Night doth seem.

The students of the Barbet school attended the classes of the Lycée St. Louis. In spite of his willingness and his passionate love of study, Louis was overcome with despair at being away from home. Never was homesickness more acute. “If I could only get a whiff of the tannery yard,” he would say to Jules Vercel, “I feel I should be cured.” M. Barbet endeavoured in vain to amuse and turn the thoughts of this lad of fifteen so absorbed in his sorrow. At last he thought it his duty to warn the parents of this state of mind, which threatened to become morbid.

One morning in November Louis Pasteur was told with an air of mystery that he was wanted. “They are waiting for you close by,” said the messenger, indicating a small café at the corner of the street. Louis entered and found a man sitting at a small table at the back of the shop, his face in his hands. It was his father. “I have come to fetch you,” he said simply. No explanations were necessary; the father and son understood each other’s longings.

What took place in Pasteur’s mind when he found himself again at Arbois? After the first few days of relief and joy, did he feel, when he went back to Arbois college, any regret, not to say remorse, at not having overcome his homesickness? Was he discouraged by the prospect of a restricted career in that small town? Little is known of that period when his will had been mastered by his feelings; but from the indecision of his daily life we may hazard a guess at the disquieted state of his mind at this time. At the beginning of that year (1839) he returned for a time to his early tastes; he went back to his coloured chalks, left aside for the last eighteen months, ever since one holiday time when he had drawn Captain Barbier, proudly wearing his uniform, and with the high colour of excellent health.

He soon got beyond the powers of his drawing master, M. Pointurier, a good man who does not seem to have seen any scientific possibilities in the art of drawing.

Louis’ pastel drawings soon formed a portrait gallery of friends. An old cooper of seventy, Father Gaidot, born at Dôle, but now living at Arbois, had his turn. Gaidot appears in a festive costume, a blue coat and a yellow waistcoat, very picturesque with his wrinkled forehead and close-shaven cheeks. Then there are all the members of a family named Roch. The father and the son are drawn carefully, portraits such as are often seen in country villages; but the two daughters Lydia and Sophia are more delicately pencilled; they live again in the youthful grace of their twenty summers. Then we have a notary, the wide collar of a frock coat framing his rubicund face; a young woman in white; an old nun of eighty-two in a fluted cap, wearing a white hood and an ivory cross; a little boy of ten in a velvet suit, a melancholy-looking child, not destined to grow to manhood. Pasteur obligingly drew any one who wished to have a portrait. Among all these pastels, two are really remarkable. The first represents, in his official garb, a M. Blondeau, registrar of mortgages, whose gentle and refined features are perfectly delineated. The other is the portrait of a mayor of Arbois, M. Pareau; he wears his silver-embroidered uniform, with a white stock. The cross of the Legion of Honour and the tricolour scarf are discreetly indicated. The whole interest is centred in the smiling face, with hair brushed up à la Louis Philippe, and blue eyes harmonizing with a blue ground.

The compliments of this local dignitary and Romanet’s renewed counsels at the end of the year—when Pasteur took more school prizes than he could carry—reawakened within him the ambition for the Ecole Normale.

There was no “philosophy”[5] class in the college of Arbois, and a return to Paris seemed formidable. Pasteur resolved to go to the college at Besançon, where he could go on with his studies, pass his baccalauréat and then prepare for the examinations of the Ecole Normale. Besançon is only forty kilometres from Arbois, and Joseph Pasteur was in the habit of going there several times a year to sell some of his prepared skins. This was by far the wisest solution of the problem.

On his arrival at the Royal College of Franche Comté Pasteur found himself under a philosophy master, M. Daunas, who had been a student at the Ecole Normale and was a graduate of the University; he was young, full of eloquence, proud of his pupils, of awakening their faculties and directing their minds. The science master, M. Darlay, did not inspire the same enthusiasm; he was an elderly man and regretted the good old times when pupils were less inquisitive. Pasteur’s questions often embarrassed him. Louis’ reputation as a painter satisfied him no longer, though the portrait he drew of one of his comrades was exhibited. “All this does not lead to the Ecole Normale,” he wrote to his parents in January, 1840. “I prefer a first place at college to 10,000 praises in the course of conversation.... We shall meet on Sunday, dear father, for I believe there is a fair on Monday. If we see M. Daunas, we will speak to him of the Ecole Normale. Dear sisters, let me tell you again, work hard, love each other. When one is accustomed to work it is impossible to do without it; besides, everything in this world depends on that. Armed with science, one can rise above all one’s fellows.... But I hope all this good advice to you is superfluous, and I am sure you spend many moments every day learning your grammar. Love each other as I love you, while awaiting the happy day when I shall be received at the Ecole Normale.” Thus was his whole life filled with tenderness as well as with work. He took the degree of “bachelier ès lettres” on August 29, 1840. The three examiners, doctors “ès lettres,” put down his answers as “good in Greek on Plutarch and in Latin on Virgil, good also in rhetoric, medicine, history and geography, good in philosophy, very good in elementary science, good in French composition.”

At the end of the summer holidays the headmaster of the Royal College of Besançon, M. Répécaud, sent for him and offered him the post of preparation master. Certain administrative changes and an increased number of pupils were the reason of this offer, which proved the master’s esteem for Pasteur’s moral qualities, his first degree not having been obtained with any particular brilliancy.

The youthful master was to be remunerated from the month of January, 1841. A student in the class of special mathematics, he was his comrades’ mentor during preparation time. They obeyed him without difficulty; simple and yet serious-minded, his sense of individual dignity made authority easy to him. Ever thoughtful of his distant home, he strengthened the influence of the father and mother in the education of his sisters, who had not so great a love of industry as he had. On November 1, 1840—he was not eighteen yet—pleased to hear that they were making some progress, he wrote the following, which, though slightly pedantic, reveals the warmth of his feelings—“My dear parents, my sisters, when I received at the same time the two letters that you sent me I thought that something extraordinary had happened, but such was not the case. The second letter you wrote me gave me much pleasure; it tells me that—perhaps for the first time—my sisters have willed. To will is a great thing, dear sisters, for Action and Work usually follow Will, and almost always Work is accompanied by success. These three things, Will, Work, Success, fill human existence. Will opens the door to success both brilliant and happy; Work passes these doors, and at the end of the journey Success comes to crown one’s efforts. And so, my dear sisters, if your resolution is firm, your task, be it what it may, is already begun; you have but to walk forward, it will achieve itself. If perchance you should falter during the journey, a hand would be there to support you. If that should be wanting, God, who alone could take that hand from you, would Himself accomplish its work.... May my words be felt and understood by you, dearest sisters. I impress them on your hearts. May they be your guide. Farewell. Your brother.”

The letters he wrote, the books he loved, the friends he chose, bear witness to the character of Pasteur in those days of early youth. As he now felt, after the discouraging trial he had gone through in Paris, that the development of the will should hold the first place in education, he applied all his efforts to the bringing out of this leading force. He was already grave and exceptionally matured; he saw in the perfecting of self the great law of man, and nothing that could assist in that improvement seemed to him without importance. Books read in early life appeared to him to have an almost decisive influence. In his eyes a good book was a good action constantly renewed, a bad one an incessant and irreparable fault.

There lived at that time in Franche Comté an elderly writer, whom Sainte Beuve considered as the ideal of the upright man and of the man of letters. His name was Joseph Droz, and his moral doctrine was that vanity is the cause of many wrecked and aimless lives, that moderation is a form of wisdom and an element of happiness, and that most men sadden and trouble their lives by causeless worry and agitation. His own life was an example of his precepts of kindliness and patience, and was filled to the utmost with all the good that a pure literary conscience can bestow; he was all benevolence and cordiality. It seemed natural that he should publish one after another numberless editions of his Essay on the Art of being Happy.

“I have still,” wrote Pasteur to his parents, “that little volume of M. Droz which he was kind enough to lend me. I have never read anything wiser, more moral or more virtuous. I have also another of his works; nothing was ever better written. At the end of the year I shall bring you back these books. One feels in reading them an irresistible charm which penetrates the soul and fills it with the most exalted and generous feelings. There is not a word of exaggeration in what I am writing. Indeed I take his books with me to the services on Sundays to read them, and I believe that in so acting, in spite of all that thoughtless bigotry might say, I am conforming to the very highest religious ideas.”

Those ideas Droz might have summarized simply by Christ’s words, “Love ye one another.” But this was a time of circumlocution. Young people demanded of books, of discourses, of poetry, a sonorous echo of their own secret feelings. In the writings of the Besançon moralist, Pasteur saw a religion such as he himself dreamed of, a religion free from all controversy and all intolerance, a religion of peace, love and devotion.

A little later, Silvio Pellico’s Miei Prigioni developed in him an emotion which answered to his instinctive sympathy for the sorrows of others. He wrote advising his sisters to read “that interesting work, where you breathe with every page a religious perfume which exalts and ennobles the soul.” In reading Miei Prigioni his sisters would light upon a passage on fraternal love and all the deep feelings which it represents.

“For my sisters,” he wrote in another letter, “I bought, a few days ago, a very pretty book; I mean by very pretty something very interesting. It is a little volume which took the Montyon[6] prize a few years ago, and it is called, Picciola. How could it have deserved the Montyon prize,” he added, with an edifying respect for the decisions of the Academy, “if the reading of it were not of great value?”

“You know,” he announced to his parents when his appointment was definitely settled, “that a supplementary master has board and lodging and 300 francs a year!” This sum appeared to him enormous. He added, on January 20: “At the end of this month money will already be owing to me; and yet I assure you I am not really worth it.”

Pleased with this situation, though such a modest one, full of eagerness to work, he wrote in the same letter: “I find it an excellent thing to have a room of my own; I have more time to myself, and I am not interrupted by those endless little things that the boys have to do, and which take up a good deal of time. Indeed I am already noticing a change in my work; difficulties are getting smoothed away because I have more time to give to overcoming them; in fact I am beginning to hope that by working as I do and shall continue to do I may be received with a good rank at the Ecole. But do not think that I am overworking myself at all; I take every recreation necessary to my health.”

Besides his ordinary work, he had been entrusted with the duty of giving some help in mathematics and physical science to the youths who were reading for their baccalauréat.

As if reproaching himself with being the only member of the family who enjoyed the opportunity of learning, he offered to pay for the schooling of his youngest sister Josephine in a girls’ college at Lons-le-Saulnier. He wrote, “I could easily do it by giving private lessons. I have already refused to give some to several boys at 20 or 25 fr. a month. I refused because I have not too much time to give to my work.” But he was quite disposed to waive this motive in deference to superior judgment. His parents promised to think over this fraternal wish, without however accepting his generous suggestion, offering even to supplement his small salary of 24 francs a month by a little allowance, in case he wished for a few private lessons to prepare himself more thoroughly for the Ecole Normale. They quite recognized his right to advise; and—as he thought that his sister should prepare herself beforehand for the class she was to enter—he wrote to his mother with filial authority, “Josephine should work a good deal until the end of the year, and I would recommend to Mother that she should not continually be sent out on errands; she must have time to work.”

Michelet, in his recollections, tells of his hours of intimacy with a college friend named Poinsat, and thus expresses himself: “It was an immense, an insatiable longing for confidences, for mutual revelations.” Pasteur felt something of the sort for Charles Chappuis, a philosophie student at Besançon college. He was the son of a notary at St. Vit, one of those old-fashioned provincial notaries, who, by the dignity of their lives, their spirit of wisdom, the perpetual preoccupation of their duty, inspired their children with a sense of responsibility. His son had even surpassed his father’s hopes. Of this generous, gentle-faced youth there exists a lithograph signed “Louis Pasteur.” A book entitled Les Graveurs du XIXᵐᵉ Siècle mentions this portrait, giving Pasteur an unexpected form of celebrity. Before the Graveurs, the Guide de l’Amateur des Œuvres d’Art had already spoken of a pastel drawing discovered in the United States near Boston. It represents another schoolfellow of Pasteur’s, who, far from his native land, carefully preserved the portrait of Chappuis as well as his own. Everything that friendship can give in strength and disinterestedness, everything that, according to Montaigne—who knew more about it even that Michelet—“makes souls merge into each other so that the seam which originally joined them disappears,” was experienced by Pasteur and Chappuis. Filial piety, brotherly solicitude, friendly confidences—Pasteur knew the sweetness of all these early human joys; the whole of his life was permeated with them. The books he loved added to this flow of generous emotions. Chappuis watched and admired this original nature, which, with a rigid mind made for scientific research and always seeking the proof of everything, yet read Lamartine’s Meditations with enthusiasm. Differing in this from many science students, who are indifferent to literature—just as some literature students affect to disdain science—Pasteur kept for literature a place apart. He looked upon it as a guide for general ideas. Sometimes he would praise to excess some writer or orator merely because he had found in one page or in one sentence the expression of an exalted sentiment. It was with Chappuis that he exchanged his thoughts, and together they mapped out a life in common. When Chappuis went to Paris, the better to prepare himself for the Ecole Normale, Pasteur felt an ardent desire to go with him. Chappuis wrote to him with that open spontaneity which is such a charm in youth, “I shall feel as if I had all my Franche Comté with me when you are here.” Pasteur’s father feared a crisis like that of 1838, and, after hesitating, refused his consent to an immediate departure. “Next year,” he said.

In October, 1841, though still combining the functions of master and student, Pasteur resumed his attendance of the classes for special mathematics. But he was constantly thinking of Paris, “Paris, where study is deeper.” One of Chappuis’ comrades, Bertin, whom Pasteur had met during the holidays, had just entered the Ecole Normale at the head of the list after attending in Paris a class of special mathematics.

“If I do not pass this year,” Pasteur wrote to his father on November 7, “I think I should do well to go to Paris for a year. But there is time to think of that and of the means of doing so without spending too much, if the occasion should arise. I see now what great advantage there is in giving two years to mathematics; everything becomes clearer and easier. Of all our class students who tried this year for the Ecole Polytechnique and the Ecole Normale, not a single one has passed, not even the best of them, a student who had already done one year’s mathematics at Lyons. The master we have now is very good. I feel sure I shall do a great deal this year.”

He was twice second in his class; once he was first in physics. “That gives me hope for later on,” he said. He wrote about another mathematical competition, “If I get a good place it will be well deserved, for this work has given me a pretty bad headache; I always do get one, though, whenever we have a competition.” Then, fearful of alarming his parents, he hastily adds, “But those headaches never last long, and it is only an hour and a half since we left off.”

Anxious to stifle by hard work his growing regrets at not having followed Chappuis to Paris, Pasteur imagined that he might prepare himself for the Ecole Polytechnique as well as for the Ecole Normale. One of his masters, M. Bouché, had led him to hope that he might be successful. “I shall try this year for both schools,” Pasteur wrote to his friend (January 22, 1842). “I do not know whether I am right in deciding to do so. One thing tells me that I am wrong: it is the idea that we might thus be parted; and when I think of that, I firmly believe that I cannot possibly be admitted this year into the Ecole Polytechnique. I feel quite superstitious about it. I have but one pleasure, your letters and those from my family. Oh! do write often, very long letters!”

Chappuis, concerned at this sudden resolve, answered in terms that did credit to his heart and youthful wisdom. “Consult your tastes, think of the present, of the future. You must think of yourself; it is your own fate that you have to direct. There is more glitter on the one side; on the other the gentle quiet life of a professor, a trifle monotonous perhaps, but full of charm for him who knows how to enjoy it. You too appreciated it formerly, and I learned to do so when we thought we should both go the same way. Anyhow, go where you think you will be happy, and think of me sometimes. I hope your father will not blame me. I believe he looks upon me as your evil genius. These last holidays I wanted you to come to me, then I advised you to go to Paris; each time your father created some obstacle! But do what he wishes, and never forget that it is perhaps because he loves you too much that he never does what you ask him.”

Pasteur soon thought no more of his Polytechnic fancy, and gave himself up altogether to his preparation for the Ecole Normale. But the study of mathematics seemed to him dry and exhausting. He wrote in April, “One ends by having nothing but figures, formulas and geometrical forms before one’s eyes.... On Thursday I went out and I read a charming story, which, much to my astonishment, made me weep. I had not done such a thing for years. Such is life.”

On August 13, 1842, he went up for his examination (baccalauréat ès sciences) before the Dijon Faculty. He passed less brilliantly even than he had done for the baccalauréat ès lettres. In chemistry he was only put down as “médiocre.” On August 26 he was declared admissible to the examinations for the Ecole Normale. But he was only fifteenth out of twenty-two candidates. He considered this too low a place, and resolved to try again the following year. In October, 1842, he started for Paris with Chappuis. On the eve of his departure Louis drew a last pastel, a portrait of his father. It is a powerful face, with observation and meditation apparent in the eyes, strength and caution in the mouth and chin.

Pasteur arrived at the Barbet Boarding School, no longer a forlorn lad, but a tall student capable of teaching and engaged for that purpose. He only paid one-third of the pupil’s fees, and in return had to give to the younger pupils some instruction in mathematics every morning from six to seven. His room was not in the school, but in the same Impasse des Feuillantines; two pupils shared it with him.

“Do not be anxious about my health and work,” he wrote to his friends a few days after his arrival. “I need hardly get up till 5.45; you see it is not so very early.” He went on outlining the programme of his time. “I shall spend my Thursdays in a neighbouring library with Chappuis, who has four hours to himself on that day. On Sundays we shall walk and work a little together; we hope to do some Philosophy on Sundays, perhaps too on Thursdays; I shall also read some literary works. Surely you must see that I am not homesick this time.”

Besides attending the classes of the Lycée St. Louis, he also went to the Sorbonne[7] to hear the Professor, who, after taking Gay-Lussac’s place in 1832, had for the last ten years delighted his audience by an eloquence and talent which opened boundless horizons before every mind.

In a letter dated December 9, 1842, Pasteur wrote, “I attend at the Sorbonne the lectures of M. Dumas, a celebrated chemist. You cannot imagine what a crowd of people come to these lectures. The room is immense, and always quite full. We have to be there half an hour before the time to get a good place, as you would in a theatre; there is also a great deal of applause; there are always six or seven hundred people.” Under this rostrum, Pasteur became, in his own words, a “disciple” full of the enthusiasm inspired by Dumas.

Happy in this industrious life, he wrote in response to an expression of his parents’ provincial uneasiness as to the temptations of the Latin Quarter. “When one wishes to keep straight, one can do so in this place as well as in any other; it is those who have no strength of will that succumb.”

He made himself so useful at Barbet’s that he was soon kept free of all expense. But the expenses of his Parisian life are set out in a small list made about that time. His father wished him to dine at the Palais Royal on Thursdays and Sundays with Chappuis, and the price of each of those dinners came to a little less than two francs. He had, still with the inseparable Chappuis, gone four times to the theatre and once to the opera. He had also hired a stove for his stone-floored room; for eight francs he had bought some firewood, and also a two-franc cloth for his table, which he said had holes in it, and was not convenient to write on.

At the end of the school year, 1843, he took at the Lycée St. Louis two “Accessits,”[8] and one first prize in physics, and at the “Concours Général”[9] a sixth “Accessit” in physics. He was admitted fourth on the list to the Ecole Normale. He then wrote from Arbois to M. Barbet, telling him that on his half-holidays he would give some lessons at the school of the Impasse des Feuillantines as a small token of his gratitude for past kindness. “My dear Pasteur,” answered M. Barbet, “I accept with pleasure the offer you have made me to give to my school some of the leisure that you will have during your stay at the Ecole Normale. It will indeed be a means of frequent and intimate intercourse between us, in which we shall both find much advantage.”

Pasteur was in such a hurry to enter the Ecole Normale that he arrived in Paris some days before the other students. He solicited permission to come in as another might have begged permission to come out. He was readily allowed to sleep in the empty dormitory. His first visit was to M. Barbet. The Thursday half-holiday, usually from one to seven, was now from one to eight. “There is nothing more simple,” he said, “than to come regularly at six o’clock on Thursdays and give the schoolboys a physical science class.”

“I am very pleased,” wrote his father, “that you are giving lessons at M. Barbet’s. He has been so kind to us that I was anxious that you should show him some gratitude; be therefore always most obliging towards him. You should do so, not only for your own sake, but for others; it will encourage him to show the same kindness to other studious young men, whose future might depend upon it.”

Generosity, self-sacrifice, kindliness even to unknown strangers, cost not the least effort to the father and son, but seemed to them the most natural thing possible. Just as their little house at Arbois was transformed by a ray of the ideal, the broken down walls of the old Ecole Normale—then a sort of annexe of the Louis Le Grand college, and looking, said Jules Simon, like an old hospital or barracks—reflected within them the ideas and sentiments which inspire useful lives. Joseph Pasteur wrote (Nov. 18, 1843): “The details you give me on the way your work is directed please me very much; everything seems organized so as to produce distinguished scholars. Honour be to those who founded this School.” Only one thing troubled him, he mentioned it in every letter. “You know how we worry about your health; you do work so immoderately. Are you not injuring your eyesight by so much night work? Your ambition ought to be satisfied now that you have reached your present position!” He also wrote to Chappuis: “Do tell Louis not to work so much; it is not good to strain one’s brain. That is not the way to succeed but to compromise one’s health.” And with some little irony as to the cogitations of Chappuis the philosopher: “Believe me, you are but poor philosophers if you do not know that one can be happy even as a poor professor in Arbois College.”

Another letter, December, 1843, to his son this time: “Tell Chappuis that I have bottled some 1834 bought on purpose to drink the health of the Ecole Normale during the next holidays. There is more wit in those 100 litres than in all the books on philosophy in the world; but, as to mathematical formulæ, there are none, I believe. Mind you tell him that we shall drink the first bottle with him. Remain two good friends.”

Pasteur’s letters during this first period at the Normale have been lost, but his biography continues without a break, thanks to the letters of his father. “Tell us always about your studies, about your doings at Barbet’s. Do you still attend M. Pouillet’s lectures, or do you find that one science hampers the other? I should think not; on the contrary, one should be a help to the other.” This observation should be interesting to a student of heredity; the idea casually mentioned by the father was to receive a vivid demonstration in the life-work of the son.

CHAPTER II
1844—1849

Pasteur often spent his leisure moments in the library of the Ecole Normale. Those who knew him at that time remember him as grave, quiet, almost shy. But under these reflective characteristics lay the latent fire of enthusiasm. The lives of illustrious men, of great scientists, of great patriots inspired him with a generous ardour. To this ardour he added a great eagerness of mind; whether studying a book, even a commonplace one—for he was so conscientious that he did not even know what it was to “skim” through a book—or coming away from one of J. B. Dumas’ lectures, or writing his student’s notes in his small fine handwriting, he was always thirsting to learn more, to devote himself to great researches. There seemed to him no better way of spending a holiday than to be shut up all Sunday afternoon at the Sorbonne laboratory or coaxing a private lesson from the celebrated Barruel, Dumas’ curator.

Chappuis—anxious to obey the injunctions of Pasteur’s father, who in every letter repeated “Do not let him work too much!” desirous also of enjoying a few hours’ outing with his friend—used to wait philosophically, sitting on a laboratory stool, until the experiments were over. Conquered by this patient attitude and reproachful silence Pasteur would take off his apron, saying half angrily, half gratefully, “Well, let us go for a walk.” And, when they were out in the street, the same serious subjects of conversation would inevitably crop up—classes, lectures, readings, etc.

One day, in the course of those long talks in the gardens of the Luxembourg, Pasteur carried Chappuis with him very far away from philosophy. He began to talk of tartaric acid and of paratartaric acid. The former had been known since 1770, thanks to the Swedish chemist Scheele, who discovered it in the thick crusty formations within wine barrels called “tartar”; but the latter was disconcerting to chemists. In 1820 an Alsatian manufacturer, Kestner, had obtained by chance, whilst preparing tartaric acid in his factory at Thann, a very singular acid which he was unable to reproduce in spite of various attempts. He had kept some of it in stock. Gay-Lussac, having visited the Thann factory in 1826, studied this mysterious acid; he proposed to call it racemic acid. Berzelius studied it in his turn, and preferred to call it paratartaric. Either name may be adopted; it is exactly the same thing: men of letters or in society are equally frightened by the word paratartaric or racemic. Chappuis certainly was when Pasteur repeated to him word for word a paragraph by a Berlin chemist and crystallographer named Mitscherlich. Pasteur had pondered over this paragraph until he knew it by heart; often indeed, absorbed in reading the reports for 1844 of the Académie des Sciences, in the dark room which was then the library of the Ecole Normale, he had wondered if it were possible to get over a difficulty which seemed insurmountable to scientists such as Mitscherlich and Biot. This paragraph related to two saline combinations—tartrate and paratartrate of soda or ammonia—and may be epitomized as follows: in these two substances of similar crystalline form, the nature and number of the atoms, their arrangement and distances are the same. Yet dissolved tartrate rotates the plane of polarized light and paratartrate remains inactive.

Pasteur had the gift of making scientific problems interesting in a few words, even to minds least inclined to that particular line of thought. He rendered his listener’s attention very easy; no question surprised him and he never smiled at ignorance. Though Chappuis, absorbed in the series of lectures on philosophy given at that time by Jules Simon, was deep in a train of thought very far away from Mitscherlich’s perplexities, he gradually became interested in this optical inactivity of paratartrate, which so visibly affected his friend. Pasteur liked to look back into the history of things, giving in this way a veritable life to his explanations. Thus, à propos of the optical phenomenon which puzzled Mitscherlich, Pasteur was speaking to his friend of crystallized carbonate of lime, called Iceland spar, which presents a double refraction—that is to say: if you look at an object through this crystal, you perceive two reproductions of that object. In describing this, Pasteur was not giving to Chappuis a vague notion of some piece of crystal in a glass case, but was absolutely evoking a vision of the beautiful crystal, perfectly pure and transparent, brought from Iceland in 1669 to a Danish physicist. Pasteur almost seemed to experience the surprise and emotion of this scientist, when, observing a ray of light through this crystal, he saw it suddenly duplicated. Pasteur also spoke enthusiastically of an officer of Engineers under the First Empire, Etienne Louis Malus. Malus was studying double refraction, and holding in his hands a piece of spar crystal, when, from his room in the Rue de l’Enfer, it occurred to him to observe through the crystal the windows of the Luxembourg Palace, then lighted up by the setting sun. It was sufficient to make the crystal rotate slowly round the visual ray (as on an axis) to perceive the periodic variations in the intensity of the light reflected by the windows. No one had yet suspected that light, after being reflected under certain conditions, would acquire properties quite different from those it had before its reflection. Malus gave the name of polarized light to light thus modified (by reflection in this particular case). Scientists admitted in those days, in the theory of emission, the existence of luminous molecules, and they imagined that these molecules “suffered the same effects simultaneously when they had been reflected on glass at a certain angle.... They were all turned in the same direction.” Pouillet, speaking of this discovery of Malus in the class on physics that Pasteur attended, explained that the consequent persuasion was “that those molecules had rotatory axes and poles, around which their movements could be accomplished under certain influences.”

Pasteur spoke feverishly of his regrets that Malus should have died at thirty-seven in the midst of his researches; of Biot, and of Arago, who became illustrious in the path opened by Malus. He explained to Chappuis that, by means of a polarizing apparatus, it could be seen that certain quartz crystals deflected to the right the plane of polarized light, whilst others caused it to turn to the left. Chappuis also learned that some natural organic material, such as solutions of sugar or of tartaric acid, when placed in such an apparatus, turned to the right the plane of polarization, whilst others, like essence of turpentine or quinine, deflected it to the left; whence the expression “rotatory polarization.”

These would seem dry researches, belonging altogether to the domain of science. And yet, thanks to the saccharimeter, which is a polarizing apparatus, a manufacturer can ascertain the quantity of pure sugar contained in the brown sugar of commerce, and a physiologist can follow the progress of diabetes.

Chappuis, who knew what powers of investigation his friend could bring to bear on the problem enunciated by Mitscherlich, thought with regret that the prospect of such examinations as that for the licence and for the agrégation did not allow Pasteur to concentrate all his forces on such a special scientific point. But Pasteur was resolved to come back definitely to this subject as soon as he should have become “docteur ès sciences.”

When writing to his father he did not dwell upon tartrate and paratartrate; but his ambition was palpable. He was ever eager to do double work, to go up for his examination at the very earliest. “Before being a captain,” answered the old sergeant-major, “you must become a lieutenant.”

These letters give one the impression of living amongst those lives, perpetually reacting upon each other. The thoughts of the whole family were centred upon the great School, where that son, that brother, was working, in whom the hopes of each were placed. If one of his bulky letters with the large post mark was too long in coming, his father wrote to reproach him gently: “Your sisters were counting the days. Eighteen days, they said! Louis has never kept us waiting so long! Can he be ill? It is a great joy to me,” adds the father, “to note your attachment to each other. May it always remain so.”

The mother had no time to write much; she was burdened with all the cares of the household and with keeping the books of the business. But she watched for the postman with a tender anxiety increased by her vivid imagination. Her thoughts were ever with the son whom she loved, not with a selfish love, but for himself, sharing his happiness in that he was working for a useful career.

So, between that corner in the Jura and the Ecole Normale, there was a continual exchange of thoughts; the smallest incidents of daily life were related. The father, knowing that he should inform the son of the fluctuations of the family budget, spoke of his more or less successful sales of leathers at the Besançon fair. The son was ever hunting in the progress of industry anything that could tend to lighten the father’s heavy handicraft. But though the father declared himself ready to examine Vauquelin’s new tanning process, which obviated the necessity of keeping the skins so long in the pits, he asked himself with scrupulous anxiety whether leathers prepared in that way would last as long as the others. Could he safely guarantee them to the shoemakers, who were unanimous in praising the goods of the little tannery-yard, but alas equally unanimous in forgetting to reward the disinterested tanner by prompt payment? He supplied his family with the necessaries of life: what more did he want? When he had news of his Normalien he was thoroughly happy. He associated himself with his son’s doings, sharing his enthusiasm over Dumas’ lectures, and taking an interest in Pouillet’s classes: Pouillet was a Franc-Comtois, and had been a student at the Ecole Normale; he was now Professor of Physics at the Sorbonne and a member of the Institut.[10] When Balard, a lecturer at the Ecole, was nominated to the Académie des Sciences, Louis told his father of it with the delight of an admiring pupil.

Like J. B. Dumas, Balard had been an apothecary’s pupil. When he spoke of their humble beginnings, Dumas was wont to say rather pompously—“Balard and I were initiated into our scientific life under the same conditions.” When, at the age of forty-two, he was made a member of the Institute, Balard could not contain his joy; he was quite a Southerner in his language and gestures, and the adjective exubérant might have been invented for him. But this same Southerner, ever on the move as he was, belonged to a special race: he always kept his word. “I was glad to note your pleasure at this nomination,” wrote Joseph Pasteur to his son; “it proves that you are grateful to your masters.” About that same time the headmaster of Arbois College, M. Romanet, used to read out to the older boys the letters, always full of gratitude, which he received from Louis Pasteur. These letters reflected life in Paris, such as Pasteur understood it—a life of hard work and exalted ambition. M. Romanet, in one of his replies, asked him to become librarian in partibus for the college and to choose and procure books on science and literature. The headmaster also begged of the young man some lectures for the rhétorique class during the holidays. “It would seem to the boys like an echo of the Sorbonne lectures! And you would speak to us of our great scientific men,” added M. Romanet, “amongst whom we shall one day number him who once was one of our best pupils and will ever remain one of our best friends.”

A corresponding member of Arbois College, and retained as vacation lecturer, Pasteur now undertook a yet more special task. He had often heard his father deplore his own lack of instruction, and knew well the elder man’s desire for knowledge. By a touching exchange of parts, the child to whom his father had taught his alphabet now became his father’s teacher; but with what respect and what delicacy did this filial master express himself! “It is in order that you may be able to help Josephine that I am sending you this work to do.” He took most seriously his task of tutor by correspondence; the papers he sent were not always easy. His father wrote (Jan. 2, 1845)—“I have spent two days over a problem which I afterwards found quite easy; it is no trifle to learn a thing and teach it directly afterwards.” And a month later: “Josephine does not care to rack her brains, she says; however I promise you that you will be pleased with her progress by the next holidays.”

The father would often sit up late at night over rules of grammar and mathematical problems, preparing answers to send to his boy in Paris.

Some Arboisians, quite forgotten now, imagined that they would add lustre to the local history. General Baron Delort, a peer of France,[11] aide de camp to Louis Philippe, Grand Cross of the Legion of Honour and the first personage in Arbois—where he beguiled his old age by translating Horace—used to go across the Cuisance bridge without so much as glancing at the tannery where the Pasteur family lived. Whilst the general in his thoughts bequeathed to the town of Arbois his books, his papers, his decorations, even his uniform, he was far from foreseeing that the little dwelling by the bridge would one day become the cynosure of all eyes.

Months went by and happy items of news succeeded one another. The Normalien was chiefly interested in the transformations of matter, and was practising in order to become capable of assisting in experiments; difficulties only stimulated him. At the chemistry class that he attended, the process of obtaining phosphorus was merely explained, on account of the length of time necessary to obtain this elementary substance; Pasteur, with his patience and desire for proven knowledge, was not satisfied. He therefore bought some bones, burnt them, reduced them to a very fine ash, treated this ash with sulphuric acid, and carefully brought the process to its close. What a triumph it seemed to him when he had in his possession sixty grammes of phosphorus, extracted from bones, which he could put into a phial labelled “phosphorus.” This was his first scientific joy.

Whilst his comrades ironically (but with some discernment) called him a “laboratory pillar,” some of them, more intent upon their examinations, were getting ahead of him.—M. Darboux, the present “doyen” of the Faculty[12] of Science, finds in the Sorbonne registers that Pasteur was placed 7th at the licence examination; two other students having obtained equal marks with him, the jury (Balard, Dumas and Delafosse), mentioned his name after theirs.

Those who care for archives would find in the Journal Général de l’Instruction Publique of September 17, 1846, a report of the agrégation[13] competition (physical science). Out of fourteen candidates only four passed and Pasteur was the third. His lessons on physics and chemistry caused the jury to say, “He will make an excellent professor.”

Many Normaliens of that time fancied themselves called to a destiny infinitely superior to his. Some of them, in later times, used to complacently allude to this momentary superiority when speaking to their pupils. Of all Pasteur’s acquaintances Chappuis was the only one who divined the future. “You will see what Pasteur will be,” he used to say, with an assurance generally attributed to friendly partiality. Chappuis—Pasteur’s confidant—was well aware of his friend’s powers of concentration.

Balard also realised this; he had the happy idea of taking the young agrégé into his laboratory, and intervened vehemently when the Minister of Public Instruction desired—a few months later—that Pasteur should teach physics in the Tournon Lycée. It would be rank folly, Balard declared, to send 500 kilometres away from Paris a youth who only asked for the modest title of curator, and had no ambition but to work from morning till night, preparing for his doctor’s degree. There would be time to send him away later on. It was impossible to resist this torrent of words founded on solid sense. Balard prevailed.

Pasteur was profoundly grateful to him for preserving him from exile to the little town in Ardèche; and, as he added to his Franc-Comtois patience and reflective mind a childlike heart and deep enthusiasm, he was delighted to remain with a master like Balard, who had become celebrated, at the age of twenty-four, as the discoverer of bromin.

At the end of 1846, a newcomer entered Balard’s laboratory, a strange delicate-looking man, whose ardent eyes were at the same time proud and yet anxious. This man, a scientist and a poet, was a professor of the Bordeaux Faculty, named Auguste Laurent. Perhaps he had had some friction with his Bordeaux chiefs, possibly he merely wished for a change; at all events, he now desired to live in Paris. Laurent was already known in the scientific world, and had recently been made a correspondent of the Académie des Sciences. He had foreseen and confirmed the theory of substitutions, formulated by Dumas as early as 1834 before the Académie. Dumas had expressed himself thus: “Chlorine possesses the singular power of seizing upon the hydrogen in certain substances, and of taking its place atom by atom.”

This theory of substitutions was—according to a simple and vivid comparison of Pasteur’s—a way of looking upon chemical bodies as upon “molecular edifices, in which one element could be replaced by another without disturbing the structure of the edifice; as if one were to replace, one by one, every stone of a monument by a new stone.” Original researches, new and bold ideas, appealed to Pasteur. But his cautious mind prevented his boldness from leading him into errors, surprises or hasty conclusions. “That is possible,” he would say, “but we must look more deeply into the subject.”

When asked by Laurent to assist him with some experiments upon certain theories, Pasteur was delighted at this suggested collaboration, and wrote to his friend Chappuis: “Even if the work should lead to no results worth publishing, it will be most useful to me to do practical work for several months with such an experienced chemist.”

It was partly due to Laurent, that Pasteur entered more deeply into the train of thought which was to lead him to grapple with Mitscherlich’s problem. “One day” (this is a manuscript note of Pasteur’s) “one day it happened that M. Laurent—studying, if I mistake not, some tungstate of soda, perfectly crystallized and prepared from the directions of another chemist, whose results he was verifying—showed me through the microscope that this salt, apparently very pure, was evidently a mixture of three distinct kinds of crystals, easily recognizable with a little experience of crystalline forms. The lessons of our modest and excellent professor of mineralogy, M. Delafosse, had long since made me love crystallography; so, in order to acquire the habit of using the goniometer, I began to carefully study the formations of a very fine series of combinations, all very easily crystallized, tartaric acid and the tartrates.” He appreciated any favourable influence on his work; we find in the same note: “Another motive urged me to prefer the study of those particular forms. M. de la Provostaye had just published an almost complete work concerning them; this allowed me to compare as I went along my own observations with those, always so precise, of that clever scientist.”

Pasteur and Laurent’s work in common was interrupted. Laurent was appointed as Dumas’ assistant at the Sorbonne. Pasteur did not dwell upon his own disappointment, but rejoiced to see honour bestowed upon a man whom he thought worthy of the first rank. Some judges have thought that Laurent, in his introductory lesson, was too eager to expound his own ideas; but is not every believer an apostle? When a mind is full of ideas, it naturally overflows. It is probable that Pasteur in Laurent’s place would have kept his part as an assistant more in the background. He did not give vent to the slightest criticism, but wrote to Chappuis. “Laurent’s lectures are as bold as his writings, and his lessons are making a great sensation amongst chemists.” Whether one of criticism or of approbation, this sensation was a living element of success. In order to answer some insinuations concerning Laurent’s ambition and constant thirst for change, Pasteur proclaimed in his thesis on chemistry how much he had been “enlightened by the kindly advice of a man so distinguished, both by his talent and by his character.”

This essay was entitled “Researches into the saturation capacity of arsenious acid. A study of the arsenites of potash, soda and ammonia.” This, to Pasteur’s mind, was but schoolboy work. He had not yet, he said, enough practice and experience in laboratory work. “In physics,” he wrote to Chappuis, “I shall only present a programme of some researches that I mean to undertake next year, and that I merely indicate in my essay.”

This essay on physics was a “Study of phenomena relative to the rotatory polarization of liquids.” In it he rendered full homage to Biot, pointing out the importance of a branch of science too much neglected by chemists; he added that it was most useful, in order to throw light upon certain difficult chemical problems, to obtain the assistance of crystallography and physics. “Such assistance is especially needed in the present state of science.”

These two essays, dedicated to his father and mother, were read on August 23, 1847. He only obtained one white ball and two red ones for each. “We cannot judge of your essays,” wrote his father, in the name of the whole family, “but our satisfaction is no less great. As to a doctor’s degree, I was far from hoping as much; all my ambition was satisfied with the agrégation.” Such was not the case with his son. “Onwards” was his motto, not from a desire for a diploma, but from an insatiable thirst for knowledge.

After spending a few days with his family and friends, he wanted to go to Germany with Chappuis to study German from morning till night. The prospect of such industrious holidays enchanted him. But he had forgotten a student’s debt. “I cannot carry out my project,” he sadly wrote, on September 3, 1847; “I am more than ruined by the cost of printing my thesis.”

On his return to Paris he shut himself up in the laboratory. “I am extremely happy. I shall soon publish a paper on crystallography.” His father writes (December 25, 1847): “We received your letter yesterday; it is absolutely satisfactory, but it could not be otherwise coming from you; you have long, indeed ever, been all satisfaction to me.” And in response to his son’s intentions of accomplishing various tasks, fully understanding that nothing will stop him: “You are doing right to make for your goal; it was only out of excessive affection that I have often written in another sense. I only feared that you might succumb to your work; so many noble youths have sacrificed their health to the love of science. Knowing you as I do, this was my only anxiety.”

After being reproved for excessive work, Louis was reprimanded for too much affection (January 1, 1848). “The presents you sent have just arrived; I shall leave it to your sisters to write their thanks. For my part, I should prefer a thousand times that this money should still be in your purse, and thence to a good restaurant, spent in some good meals that you might have enjoyed with your friends. There are not many parents, my dearest boy, who have to write such things to their son; my satisfaction in you is indeed deeper than I can express.” At the end of this same letter, the mother adds in her turn: “My darling boy, I wish you a happy new year. Take great care of your health.... Think what a worry it is to me that I cannot be with you to look after you. Sometimes I try to console myself for your absence by thinking how fortunate I am in having a child able to raise himself to such a position as yours is—such a happy position, as it seems to be from your last letter but one.” And in a strange sentence, where it would seem that a presentiment of her approaching death made worldly things appear at their true value: “Whatever happens to you, do not grieve; nothing in life is more than a chimera. Farewell, my son.”

On March 20, 1848, Pasteur read to the Académie des Sciences a portion of his treatise on “Researches on Dimorphism.” There are some substances which crystallize in two different ways. Sulphur, for instance, gives quite dissimilar crystals according to whether it is melted in a crucible or dissolved in sulphide of carbon. Those substances are called dimorphous. Pasteur, kindly aided by the learned M. Delafosse (with his usual gratefulness he mentions this in the very first pages) had made out a list—as complete as possible—of all dimorphous substances. When M. Romanet, of Arbois College, received this paper he was quite overwhelmed. “It is much too stiff for you,” he said with an infectious modesty to Vercel, Charrière, and Coulon, Pasteur’s former comrades. Perhaps the head master desired to palliate his own incompetence in the eyes of coming generations, for on the title page of the copy of Pasteur’s booklet still to be found in the Arbois library, he wrote this remark, which he signed with his initial R.:—“Dimorphisme; this word is not even to be found in the Dictionnaire de l’Académie”!! The approbation of several members of the Académie des Sciences compensated for the somewhat summary judgment of M. Romanet, whose good wishes continued to follow the rapid course of his old pupil.

After this very special study, dated at the beginning of 1848, one might imagine the graduate-curator closing his ears to all outside rumours and little concerned with political agitation, but that would be doing him an injustice. Those who witnessed the Revolution of 1848 remember how during the early days France was exalted with the purest patriotism. Pasteur had visions of a generous and fraternal Republic; the words drapeau and patrie moved him to the bottom of his soul. Lamartine[14] as a politician inspired him with an enthusiastic confidence; he delighted in the sight of a poet leader of men. Many others shared the same illusions. France, as Louis Veuillot has it, made the mistake of choosing her band-master as colonel of the regiment. Enrolled with his fellow students, Pasteur wrote thus to his parents: “I am writing from the Orleans Railway, where as a garde national[15] I am stationed. I am glad that I was in Paris during the February days[16] and that I am here still; I should be sorry to leave Paris just now. It is a great and a sublime doctrine which is now being unfolded before our eyes ... and if it were necessary I should heartily fight for the holy cause of the Republic.” “What a transformation of our whole being!” has written one who was then a candidate to the Ecole Normale, already noted by his masters for his good sense, Francisque Sarcey. “How those magical words of liberty and fraternity, this renewal of the Republic, born in the sunshine of our twentieth year, filled our hearts with unknown and absolutely delicious sensations! With what a gallant joy we embraced the sweet and superb image of a people of free men and brethren! The whole nation was moved as we were; like us, it had drunk of the intoxicating cup. The honey of eloquence flowed unceasingly from the lips of a great poet, and France believed, in childlike faith, that his word was efficacious to destroy abuses, cure evils and soothe sorrows.”

One day when Pasteur was crossing the Place du Panthéon, he saw a gathering crowd around a wooden erection, decorated with the words: Autel de la Patrie. A neighbour told him that pecuniary offerings might be laid upon this altar. Pasteur goes back to the Ecole Normale, empties a drawer of all his savings, and returns to deposit it in thankful hands.

“You say,” wrote his father on April 28, 1848, “that you have offered to France all your savings, amounting to 150 francs. You have probably kept a receipt of the office where this payment was made, with mention of the date and place?” And considering that this action should be made known, he advises him to publish it in the journal Le National or La Réforme in the following terms, “Gift to the Patrie: 150 francs, by the son of an old soldier of the Empire, Louis Pasteur of the Ecole Normale.” He wrote in the same letter, “You should raise a subscription in your school in favour of the poor Polish exiles who have done so much for us; it would be a good deed.”

After those days of national exaltation, Pasteur returned to his crystals. He studied tartrates under the influence of certain ideas that he himself liked to expound. Objects considered merely from the point of view of form, may be divided into two great categories. First, those objects which, placed before a mirror, give an image which can be superposed to them: these have a symmetrical plan; secondly, those which have an image which cannot be superposed to them: they are dissymmetrical. A chair, for instance, is symmetrical, or a straight flight of steps. But a spiral staircase is not symmetrical, its own image cannot be laid over it. If it turns to the right, its image turns to the left. In the same way the right hand cannot be superposed to the left hand, a righthand glove does not fit a left hand, and a right hand seen in a mirror gives the image of a left hand.

Pasteur noticed that the crystals of tartaric acid and the tartrates had little faces, which had escaped even the profound observation of Mitscherlich and La Provostaye. These faces, which only existed on one half of the edges or similar angles, constituted what is called a hemihedral form. When the crystal was placed before a glass the image that appeared could not be superposed to the crystal; the comparison of the two hands was applicable to it. Pasteur thought that this aspect of the crystal might be an index of what existed within the molecules, dissymmetry of form corresponding with molecular dissymmetry. Mitscherlich had not perceived that his tartrate presented these little faces, this dissymmetry, whilst his paratartrate was without them, was in fact not hemihedral. Therefore, reasoned Pasteur, the deviation to the right of the plane of polarization produced by tartrate and the optical neutrality of paratartrates would be explained by a structural law. The first part of these conclusions was confirmed; all the crystals of tartrate proved to be hemihedral. But when Pasteur came to examine the crystals of paratartrate, hoping to find none of them hemihedral, he experienced a keen disappointment. The paratartrate also was hemihedral, but the faces of some of the crystals were inclined to the right, and those of others to the left. It then occurred to Pasteur to take up these crystals one by one and sort them carefully, putting on one side those which turned to the left, and on the other those which turned to the right. He thought that by observing their respective solutions in the polarizing apparatus, the two contrary hemihedral forms would give two contrary deviations; and then, by mixing together an equal number of each kind, as no doubt Mitscherlich had done, the resulting solution would have no action upon light, the two equal and directly opposite deviations exactly neutralizing each other.

With anxious and beating heart he proceeded to this experiment with the polarizing apparatus and exclaimed, “I have it!” His excitement was such that he could not look at the apparatus again; he rushed out of the laboratory, not unlike Archimedes. He met a curator in the passage, embraced him as he would have embraced Chappuis, and dragged him out with him into the Luxembourg garden to explain his discovery. Many confidences have been whispered under the shade of the tall trees of those avenues, but never was there greater or more exuberant joy on a young man’s lips. He foresaw all the consequences of his discovery. The hitherto incomprehensible constitution of paratartaric or racemic acid was explained; he differentiated it into righthand tartaric acid, similar in every way to the natural tartaric acid of grapes, and lefthand tartaric acid. These two distinct acids possess equal and opposite rotatory powers which neutralize each other when these two substances, reduced to an aqueous solution, combine spontaneously in equal quantities.

“How often,” he wrote to Chappuis (May 5), whom he longed to have with him, “how often have I regretted that we did not both take up the same study, that of physical science. We who so often talked of the future, we did not understand. What splendid work we could have undertaken and would be undertaking now; and what could we not have done united by the same ideas, the same love of science, the same ambition! I would we were twenty and with the three years of the Ecole before us!” Always fancying that he could have done more, he often had such retrospective regrets. He was impatient to begin new researches, when a sad blow fell upon him—his mother died almost suddenly of apoplexy. “She succumbed in a few hours,” he wrote to Chappuis on May 28, “and when I reached home she had already left us. I have asked for a holiday.” He could no longer work; he remained steeped in tears and buried in his sorrow. For weeks his intellectual life was suspended.

In Paris, in the scientific world perhaps even more than in any other, everything gets known, repeated, discussed. Pasteur’s researches were becoming a subject of conversation. Balard, with his strident voice, spoke of them in the library at the Institute, which is a sort of drawing-room for talkative old Academicians. J. B. Dumas listened gravely; Biot, old Biot, then seventy-four years old, questioned the story with some scepticism. “Are you quite sure?” he would ask, his head a little on one side, his words slow and slightly ironical. He could hardly believe, on first hearing Balard, that a new doctor, fresh from the Ecole Normale, should have overcome a difficulty which had proved too much for Mitscherlich. He did not care for long conversations with Balard, and as the latter continued to extol Pasteur, Biot said, “I should like to investigate that young man’s results.”

Besides Pasteur’s deference for all those whom he looked upon as his teachers, he also felt a sort of general gratitude for their services to Science. Partly from an infinite respect and partly from an ardent desire to convince the old scientist, he wrote on his return to Paris to Biot, whom he did not know personally, asking him for an interview. Biot answered: “I shall be pleased to verify your results if you will communicate them confidentially to me. Please believe in the feelings of interest inspired in me by all young men who work with accuracy and perseverance.”

An appointment was made at the Collège de France,[17] where Biot lived. Every detail of that interview remained for ever fixed in Pasteur’s memory. Biot began by fetching some paratartaric acid. “I have most carefully studied it,” he said to Pasteur; “it is absolutely neutral in the presence of polarized light.” Some distrust was visible in his gestures and audible in his voice. “I shall bring you everything that is necessary,” continued the old man, fetching doses of soda and ammonia. He wanted the salt prepared before his eyes.

After pouring the liquid into a crystallizer, Biot took it into a corner of his room to be quite sure that no one would touch it. “I shall let you know when you are to come back,” he said to Pasteur when taking leave of him. Forty-eight hours later some crystals, very small at first, began to form; when there was a sufficient number of them, Pasteur was recalled. Still in Biot’s presence, Pasteur withdrew, one by one, the finest crystals and wiped off the mother-liquor adhering to them. He then pointed out to Biot the opposition of their hemihedral character, and divided them into two groups—left and right.

“So you affirm,” said Biot, “that your righthand crystals will deviate to the right the plane of polarization, and your lefthand ones will deviate it to the left?”

“Yes,” said Pasteur.

“Well, let me do the rest.”

Biot himself prepared the solutions, and then sent again for Pasteur. Biot first placed in the apparatus the solution which should deviate to the left. Having satisfied himself that this deviation actually took place, he took Pasteur’s arm and said to him these words, often deservedly quoted: “My dear boy, I have loved Science so much during my life, that this touches my very heart.”

“It was indeed evident,” said Pasteur himself in recalling this interview, “that the strongest light had then been thrown on the cause of the phenomenon of rotatory polarization and hemihedral crystals; a new class of isomeric substances was discovered; the unexpected and until then unexampled constitution of the racemic or paratartaric acid was revealed; in one word a great and unforeseen road was opened to science.”

Biot now constituted himself the sponsor in scientific matters of his new young friend, and undertook to report upon Pasteur’s paper entitled: “Researches on the relations which may exist between crystalline form, chemical composition, and the direction of rotatory power”—destined for the Académie des Sciences.

Biot did full justice to Pasteur; he even rendered him homage, and—not only in his own name but also in that of his three colleagues, Regnault, Balard, and Dumas—he suggested that the Académie should declare its highest approbation of Pasteur’s treatise.

Pasteur did not conceive greater happiness than his laboratory life, and yet the laboratories of that time were very unlike what they are nowadays, as we should see if the laboratories of the Collège de France, of the Sorbonne, of the Ecole Normale had been preserved. They were all that Paris could offer Europe, and Europe certainly had no cause to covet them. Nowadays the most humble college, in the smallest provincial town, would not accept such dens as the State offered (when it offered them any) to the greatest French scientists. Claude Bernard, Magendie’s curator, worked at the Collège de France in a regular cellar. Wurtz only had a lumber-room in the attics of the Dupuytren Museum. Henri Sainte Claire Deville, before he became head of the Besançon Faculty, had not even as much; he was relegated to one of the most miserable corners of the Rue Lafarge. J. B. Dumas did not care to occupy the unhealthy room reserved for him at the Sorbonne; his father-in-law, Alexandre Brongniart, having given him a small house in the Rue Cuvier, opposite the Jardin des Plantes, he had had it transformed into a laboratory and was keeping it up at his own expense. He was therefore comfortably situated, but he was exceptionally fortunate. Every scientist who had no private means to draw upon had to choose between the miserable cellars and equally miserable garrets which were all that the State could offer. And yet it was more tempting than a Professor’s chair in a College or even in a Faculty, for there one could not give oneself up entirely to one’s work.

Nothing would have seemed more natural than to leave Pasteur to his experiments. But his appointment to some definite post could no longer be deferred, in spite of Balard’s tumultuous activity. The end of the summer vacation was near, there was a vacancy: Pasteur was made a Professor of Physics at the Dijon Lycée. The Minister of Public Instruction consented to allow him to postpone his departure until the beginning of November, in order to let him finish some work begun under the eye of Biot, who thought and dreamt of nothing but these new investigations. During thirty years Biot had studied the phenomena of rotatory polarization. He had called the attention of chemists to these phenomena, but his call had been unheeded. Continuing his solitary labour, he had—in experimenting on cases both simple and complex—studied this molecular rotatory power, without suspecting that this power bore a definite relation to the hemihedral form of some crystals. And now that the old man was a witness of a triumphant sequel to his own researches, now that he had the joy of seeing a young man with a thoughtful mind and an enthusiastic heart working with him, now that the hope of this daily collaboration shed a last ray on the close of his life, Pasteur’s departure for Dijon came as a real blow. “If at least,” he said, “they were sending you to a Faculty!” He turned his wrath on to the Government officials. “They don’t seem to realize that such labours stand above everything else! If they only knew it, two or three such treatises might bring a man straight to the Institut!”

Nevertheless Pasteur had to go. M. Pouillet gave him a letter for a former Polytechnician,[18] now a civil engineer at Dijon, a M. Parandier, in which he wrote—

“M. Pasteur is a most distinguished young chemist. He has just completed some very remarkable work, and I hope it will not be long before he is sent to a first-class Faculty. I need add nothing else about him; I know no more honest, industrious, or capable young man. Help him as much as you can at Dijon; you will not regret it.”

Those first weeks away from his masters and from his beloved pursuits seemed very hard to Pasteur. But he was anxious to prove himself a good teacher. This duty appeared to him to be a noble ideal, and to involve a wide responsibility. He felt none of the self satisfaction which is sometimes a source of strength to some minds conscious of their superiority to others. He did not even do himself the justice of feeling that he was absolutely sure of his subject. He wrote to Chappuis (November 20, 1848): “I find that preparing my lessons takes up a great deal of time. It is only when I have prepared a lesson very carefully that I succeed in making it very clear and capable of compelling attention. If I neglect it at all I lecture badly and become unintelligible.”

He had both first and second year pupils; these two classes took up all his time and all his strength. He liked the second class; it was not a very large one. “They all work,” Pasteur wrote, “some very intelligently.” As to the first year class, what could he do with eighty pupils? The good ones were kept back by the bad. “Don’t you think,” he wrote, “that it is a mistake not to limit classes to fifty boys at the most? It is with great difficulty that I can secure the attention of all towards the end of the lesson. I have only found one means, which is to multiply experiments at the last moment.”

Whilst he was eagerly and conscientiously giving himself up to his new functions—not without some bitterness, for he really was entitled to an appointment in a Faculty, and he could not pursue his favourite studies—his masters were agitating on his behalf. Balard was clamouring to have him as an assistant at the Ecole Normale. Biot was appealing to Baron Thenard. This scientist was then Chairman of the Grand Council of the Université.[19] He had been a pupil of Vauquelin, a friend of Laplace, and a collaborator of Gay-Lussac; he had lectured during thirty years at the Sorbonne, at the Collège de France, and at the Ecole Polytechnique; he could truthfully boast that he had had 40,000 pupils. He was, like J. B. Dumas, a born professor. But, whilst Dumas was always self possessed and dignified in his demeanour, his very smile serious, Thenard, a native of Burgundy, threw his whole personality into his work, a broad smile on his beaming face.

He was now (1848) seventy years old, and the memory of his teaching, the services rendered to industry by his discoveries, the éclat of his name and titles contrasted with his humble origin, all combined to render him more than a Chancellor of the University; he was in fact a sort of Field Marshal of science, and all powerful. Three years previously he had much scandalized certain red-tape officials by choosing three very young men—Puiseux, Delesse, and H. Sainte Claire Deville—as professors for the new Faculty of Science at Besançon. He had accentuated this authoritative measure by making Sainte Claire Deville Dean of the Faculty. In the unknown professor of twenty-six, he had divined the future celebrated scientist.

At the end of the year 1848 Pasteur solicited the place of assistant to M. Delesse, who was taking a long leave of absence. This would have brought him near Arbois, besides placing him in a Faculty. He asked for nothing more. Thenard, who had Biot’s report in his hands, undertook to transmit to the Minister this modest and natural request. He was opposed by an unexpected argument—the presentation of assistantships belonged to each Faculty. This custom was unknown to Pasteur. Thenard was unable to overcome this routine formality. Pasteur thought that the unanimous opinion of Thenard, Biot, and Pouillet ought to have prevailed. “I can practically do nothing here,” he wrote on the sixth of December, thinking of his interrupted studies. “If I cannot go to Besançon, I shall go back to Paris as a curator.”

His father, to whom he paid a visit for the new year, persuaded him to look upon things more calmly, telling him that wisdom repudiated too much hurry. Louis deferred to his father’s opinion to the extent of writing, on January 2, 1849, to the Minister of Public Instruction, begging him to overlook his request. However, the members of the Institute who had taken up his cause did not intend to be thwarted by minor difficulties. Pasteur’s letter was hardly posted when he received an assistantship, not at the Besançon Faculty but at Strasburg, to take the place of M. Persoz, Professor of Chemistry, who was desirous of going to Paris.

Pasteur, on his arrival at Strasburg (January 15) was welcomed by the Professor of Physics, his old school friend, the Franc-Comtois Bertin. “First of all, you are coming to live with me,” said Bertin gleefully. “You could not do better; it is a stone’s throw from the Faculté.” By living with Bertin, Pasteur acquired a companion endowed with a rare combination of qualities—a quick wit and an affectionate heart. Bertin was too shrewd to be duped, and a malicious twinkle often lit up his kindly expression; with one apparently careless word, he would hit the weak point of the most self satisfied. He loved those who were simple and true, hence his affection for Pasteur. His smiling philosophy contrasted with Pasteur’s robust faith and ardent impetuosity. Pasteur admired, but did not often imitate, the peaceful manner with which Bertin, affirming that a disappointment often proved to be a blessing in disguise, accepted things as they came. In order to prove that this was no paradox, Bertin used to tell what had happened to him in 1839, when he was mathematical preparation master at the College of Luxeuil. He was entitled to 200 francs a month, but payment was refused him. This injustice did not cause him to recriminate, but he quietly tendered his resignation. He went in for the Ecole Normale examination, entered the school at the head of the list, and subsequently became Professor of Physics at the Strasburg Faculty. “If it had not been for my former disappointment, I should still be at Luxeuil.” He was now perfectly satisfied, thinking that nothing could be better than to be a Professor in a Faculty; but this absence of any sort of ambition did not prevent him from giving his teaching the most scrupulous attention. He prepared his lessons with extreme care, endeavouring to render them absolutely clear. He took great personal interest in his pupils, and often helped them with his advice in the interval between class hours. This excellent man’s whole life was spent in working for others, and to be useful was ever to him the greatest satisfaction.

Perhaps Pasteur was stimulated by Bertin’s example to give excessive importance to minor matters in his first lessons. He writes: “I gave too much thought to the style of my two first lectures, and they were anything but good; but I think the subsequent ones were more satisfactory, and I feel I am improving.” His lectures were well attended, for the numerous industries of Alsace gave to chemistry quite a place by itself.

Everything pleased him in Strasburg save its distance from Arbois. He who could concentrate his thoughts for weeks, for months even, on one subject, who could become as it were a prisoner of his studies, had withal an imperious longing for family life. His rooms in Bertin’s house suited him all the better that they were large enough for him to entertain one of his relations. His father wrote in one of his letters: “You say that you will not marry for a long time, that you will ask one of your sisters to live with you. I could wish it for you and for them, for neither of them wishes for a greater happiness. Both desire nothing better than to look after your comfort; you are absolutely everything to them. One may meet with sisters as good as they are, but certainly with none better.”

Louis Pasteur’s circle of dear ones was presently enlarged by his intimacy with another family. The new Rector of the Academy of Strasburg, M. Laurent, had arrived in October. He was no relation to the chemist of the same name, and the place he was about to take in Pasteur’s life was much greater than that held by Auguste Laurent at the time when they were working together in Balard’s laboratory.

After having begun, in 1812, as preparation master in the then Imperial College of Louis le Grand, M. Laurent had become, in 1826, head master of the College of Riom. He found at Riom more tutors than pupils; there were only three boys in the school! Thanks to M. Laurent, those three soon became one hundred and thirty-four. From Riom he was sent to Guéret, then to Saintes, to save a college in imminent danger of disappearing; there were struggles between the former head master and the Mayor, the town refused the subsidies, all was confusion. Peace immediately followed his arrival. “Those who have known him,” wrote M. Pierron in the Revue de l’Instruction Publique, “will not be surprised at such miracles coming from a man so intelligent and so active, so clever, amiable, and warm-hearted.” Wherever he was afterwards sent, at Orleans, Angoulême, Douai, Toulouse, Cahors, he worked the same charm, born of kindness. At Strasburg, he had made of the Académie a home where all the Faculty found a simple and cordial welcome. Madame Laurent was a modest woman who tried to efface herself, but whose exquisite qualities of heart and mind could not remain hidden. The eldest of her daughters was married to M. Zevort, whose name became doubly dear to the Université. The two younger ones, brought up in habits of industry and unselfishness which seemed natural to them, brightened the home by their youthful gaiety.

When Pasteur on his arrival called on this family, he had the feeling that happiness lay there. He had seen at Arbois how, through the daily difficulties of manual labour, his parents looked at life from an exalted point of view, appreciating it from that standard of moral perfection which gives dignity and grandeur to the humblest existence. In this family—of a higher social position than his own—he again found the same high ideal, and, with great superiority of education, the same simple-mindedness. When Pasteur entered for the first time the Laurent family circle, he immediately felt the delightful impression of being in a thoroughly congenial atmosphere; a communion of thoughts and feelings seemed established after the first words, the first looks exchanged between him and his hosts.

In the evening, at the restaurant where most of the younger professors dined, he heard others speak of the kindliness and strict justice of the Rector; and everyone expressed respect for his wonderfully united family.

At one of M. Laurent’s quiet evening “at homes,” Bertin was saying of Pasteur, “You do not often meet with such a hard worker; no attraction ever can take him away from his work.” The attraction now came, however, and it was such a powerful one that, on February 10, only a fortnight after his arrival, Pasteur addressed to M. Laurent the following official letter:—

“Sir,—

“An offer of the greatest importance to me and to your family is about to be made to you on my behalf; and I feel it my duty to put you in possession of the following facts, which may have some weight in determining your acceptance or refusal.

“My father is a tanner in the small town of Arbois in the Jura, my sisters keep house for him, and assist him with his books, taking the place of my mother whom we had the misfortune to lose in May last.

“My family is in easy circumstances, but with no fortune; I do not value what we possess at more than 50,000 francs, and, as for me, I have long ago decided to hand over to my sisters the whole of what should be my share. I have therefore absolutely no fortune. My only means are good health, some courage, and my position in the Université.

“I left the Ecole Normale two years ago, an agrégé in physical science. I have held a Doctor’s degree eighteen months, and I have presented to the Académie a few works which have been very well received, especially the last one, upon which a report was made which I now have the honour to enclose.

“This, Sir, is all my present position. As to the future, unless my tastes should completely change, I shall give myself up entirely to chemical research. I hope to return to Paris when I have acquired some reputation through my scientific labours. M. Biot has often told me to think seriously about the Institute; perhaps I may do so in ten or fifteen years’ time, and after assiduous work; but this is but a dream, and not the motive which makes me love Science for Science’s sake.

“My father will himself come to Strasburg to make this proposal of marriage.

“Accept, Sir, the assurance of my profound respect, etc.

“P.S.—I was twenty-six on December 27.”

A definite answer was adjourned for a few weeks. Pasteur, in a letter to Madame Laurent, wrote, “I am afraid that Mlle. Marie may be influenced by early impressions, unfavourable to me. There is nothing in me to attract a young girl’s fancy. But my recollections tell me that those who have known me very well have loved me very much.”

Of these letters, religiously preserved, fragments like the following have also been obtained. “All that I beg of you, Mademoiselle (he had now been authorised to address himself directly to her) is that you will not judge me too hastily, and therefore misjudge me. Time will show you that below my cold, shy and unpleasing exterior, there is a heart full of affection for you!” In another letter, evidently remorseful at forsaking the laboratory, he says, “I, who did so love my crystals!”

He loved them still, as is proved by an answer from Biot to a proposal of Pasteur’s. In order to spare the old man’s failing sight, Pasteur had the ingenious idea of cutting out of pieces of cork, with exquisite skill, some models of crystalline types greatly enlarged. He had tinted the edges and faces, and nothing was easier than to recognize their hemihedral character. “I accept with great pleasure,” wrote Biot on April 7, “the offer you make me of sending me a small quantity of your two acids, with models of their crystalline types.” He meant the righthand tartaric acid and the lefthand tartaric acid, which Pasteur—not to pronounce too hastily on their identity with ordinary tartaric acid—then called dextroracemic and lævoracemic.

Pasteur wished to go further; he was now beginning to study the crystallizations of formate of strontian. Comparing them with those of the paratartrates of soda and ammonia, surprised and uneasy at the differences he observed, he once exclaimed, “Ah! formate of strontian, if only I had got you!” to the immense amusement of Bertin, who long afterwards used to repeat this invocation with mock enthusiasm.

Pasteur was about to send these crystals to Biot, but the latter wrote, “Keep them until you have thoroughly investigated them.... You can depend on my wish to serve you in every circumstance when my assistance can be of any use to you, and also on the great interest with which you have inspired me.”

Regnault and Senarmont had been invited by Biot to examine the valuable samples received from Strasburg, the dextroracemic and lævoracemic acids. Biot wrote to Pasteur, “We might make up our minds to sacrifice a small portion of the two acids in order to reconstitute the racemic, but we doubt whether we should be capable of discerning it with certainty by those crystals when they are formed. You must show it us yourself, when you come to Paris for the holidays. Whilst arranging my chemical treasures, I came upon a small quantity of racemic acid which I thought I had lost. It would be sufficient for the microscopical experiments that I might eventually have to make. So if the small phial of it that you saw here would be useful to you, let me know, and I will willingly send it. In this, as in everything else, you will always find me most anxious to second you in your labours.”

This period was all happiness. Pasteur’s father and his sister Josephine came to Strasburg. The proposal of marriage was accepted, the father returned to Arbois, Josephine staying behind. She remained to keep house and to share the everyday life of her brother, whom she loved with a mixture of pride, tenderness and solicitude. In her devoted sisterly generosity, she resigned herself to the thought that her happy dream must be of short duration. The wedding was fixed for May 29.

“I believe,” wrote Pasteur to Chappuis, “that I shall be very happy. Every quality I could wish for in a wife I find in her. You will say, ‘He is in love!’ Yes, but I do not think I exaggerate at all, and my sister Josephine quite agrees with me.”

CHAPTER III
1850—1854

From the very beginning Mme. Pasteur not only admitted, but approved, that the laboratory should come before everything else. She would willingly have adopted the typographic custom of the Académie des Sciences Reports, where the word Science is always spelt with a capital S. It was indeed impossible to live with her husband without sharing his joys, anxieties and renewed hopes, as they appeared day by day reflected in his admirable eyes—eyes of a rare grey-green colour like the sparkle of a Ceylon gem. Before certain scientific possibilities, the flame of enthusiasm shone in those deep eyes, and the whole stern face was illumined. Between domestic happiness and prospective researches, Pasteur’s life was complete. But this couple, who had now shared everything for more than a year, was to suffer indirectly through the new law on the liberty of teaching.

Devised by some as an effort at compromise between the Church and the University, considered by others as a scope for competition against State education, the law of 1850 brought into the Superior Council of Public Instruction four archbishops or bishops, elected by their colleagues. In each Department[20] an Academy Council was instituted, and, in this parcelling out of University jurisdiction, the right of presence was recognized as belonging to the bishop or his delegate. But all these advantages did not satisfy those who called themselves Catholics before everything else. The rupture between Louis Veuillot on one side and, on the other, Falloux and Montalembert, the principal authors of this law, dates from that time.

“What we understood by the liberty of teaching,” wrote Louis Veuillot, “was not a share given to the Church, but the destruction of monopoly.... No alliance with the University! Away with its books, inspectors, examinations, certificates, diplomas! All that means the hand of the State laid on the liberty of the citizen; it is the breath of incredulity on the younger generation.” Confronted by the violent rejection of any attempt at reconciliation and threatened interference with the University on the part of the Church, the Government was trying to secure to itself the whole teaching fraternity.

The primary schoolmasters groaned under the heavy yoke of the prefects. “These deep politicians only know how to dismiss.... The rectors will become the valets of the prefects ...” wrote Pasteur with anger and distress in a letter dated July, 1850. After the primary schools, the attacks now reached the colleges. The University was accused of attending exclusively to Latin verse and Greek translations, and of neglecting the souls of the students. Romieu, who ironically dubbed the University “Alma Parens,” and attacked it most bitterly, seemed hardly fitted for the part of justiciary. He was a former pupil of the Ecole Polytechnique, who wrote vaudevilles until he was made a prefect by Louis Philippe. He was celebrated for various tricks which amused Paris and disconcerted the Government, much to the joy of the Prince de Joinville,[21] who loved such mystifications. After the fall of Louis Philippe, Romieu became a totally different personality. He had been supposed to take nothing seriously; he now put a tragic construction on everything. He became a prophet of woe, declaring that “gangrene was devouring the souls of eight year old children.” According to him, faith, respect, all was being destroyed; he anathematized Instruction without Education, and stigmatized village schoolmasters as “obscure apostles” charged with “preaching the doctrines of revolt.” This violence was partly oratory, but oratory does not minimize violence, it excites it. Every pamphleteer ends by being a bond-slave to his own phraseology.

When Romieu appeared in Strasburg as an Envoy Extraordinary entrusted by the Government with a general inquiry, he found that M. Laurent did not answer to that ideal of a functionary which was entertained by a certain party. M. Laurent had the very highest respect for justice; he distrusted the upstarts whose virtues were very much on the surface; he never decided on the fate of an inferior without the most painstaking inquiry; he did not look on an accidental mistake as an unpardonable fault; he refused to take any immediate and violent measures: all this caused him to be looked upon with suspicion. “The influence of the Rector” (thus ran Romieu’s official report) “is hardly, if at all, noticeable. He should be replaced by a safe man.”

The Minister of Public Instruction, M. de Parieu, had to bow before the formal wish of the Minister of the Interior, founded upon peremptory arguments of this kind. M. Laurent was offered the post of Rector at Châteauroux, a decided step downward. He refused, left Strasburg, and, with no complaint or recriminations, retired into private life at the age of fifty-five.

It was when this happy family circle was just about to be enlarged that its quiet was thus broken into by this untoward result of political agitation. M. Laurent’s youngest daughter soon after became engaged to M. Loir, a professor at the Strasburg Pharmaceutical School, who had been a student at the Ecole Normale, and who ultimately became Dean of the Faculty of Sciences at Lyons. He was then preparing, assisted by Pasteur, his “thesis” for the degree of Doctor of Science. In this he announced some new results based on the simultaneous existence of hemihedral crystalline forms and the rotatory power. He wrote, “I am happy to have brought new facts to bear upon the law that M. Pasteur has enunciated.”

“Why are you not a professor of physics or chemistry!” wrote Pasteur to Chappuis; “we should work together, and in ten years’ time we would revolutionize chemistry. There are wonders hidden in crystallization, and, through it, the inmost construction of substances will one day be revealed. If you come to Strasburg, you shall become a chemist; I shall talk to you of nothing but crystals.”

The vacation was always impatiently awaited by Pasteur. He was able to work more, and to edit the result of his researches in an extract for the Académie des Sciences. On October 2 his friend received the following letter: “On Monday I presented this year’s work to the ‘Institut.’ I read a long extract from it, and then gave a vivâ voce demonstration relative to some crystallographic details. This demonstration, which I had been specially desired to give, was quite against the prevailing customs of the Académie. I gave it with my usual delight in that sort of thing, and it was followed with great attention. Fortunately for me, the most influential members of the Académie were present. M. Dumas sat almost facing me. I looked at him several times, and he expressed by an approving nod of his head that he understood and was much interested. He asked me to his house the next day, and congratulated me. He said, amongst other things, that I was a proof that when a Frenchman took up crystallography he knew what he was about, and also that if I persevered, as he felt sure I should, I should become the founder of a school.

“M. Biot, whose kindness to me is beyond all expression, came to me after my lecture and said, ‘It is as good as it can possibly be.’ On October 14 he will give his report on my work; he declares I have discovered a very California. Do not suppose I have done anything wonderful this year. This is but a satisfactory consequence of preceding work.”

In his report (postponed until October 28) Biot was more enthusiastic. He praised the numerous and unforeseen results brought out by Pasteur within the last two years. “He throws light upon everything he touches,” he said.

To be praised by Biot was a rare favour; his diatribes were better known. In a secret committee of the Académie des Sciences (January, 1851) the Académie had to pronounce on the merits of two candidates for a professorship at the Collège de France: Balard, a professor of the Faculty of Science, chief lecturer of the Ecole Normale, and Laurent the chemist, who in order to live had been compelled to accept a situation as assayer at the Mint. Biot, with his halting step, arrived at the Committee room and spoke thus: “The title of Member of the Institute is the highest reward and the greatest honour that a French scientist can receive, but it does not constitute a privilege of inactivity that need only be claimed in order to obtain everything.... For several years, M. Balard has been in possession of two large laboratories where he might have executed any work dictated to him by his zeal, whilst nearly all M. Laurent’s results have been effected by his unaided personal efforts at the cost of heavy sacrifices. If you give the college vacancy to M. Balard, you will add nothing to the opportunities for study which he already has; but it will take away from M. Laurent the means of work that he lacks and that we have now the opportunity of providing for him. The chemical section, and indeed the whole Academy will easily judge on which side are scientific justice and the interests of future progress.”

Biot had this little speech printed and sent a copy of it to Pasteur. The incident led to a warm dispute, and Biot lost his cause. Pasteur wrote to Chappuis, “M. Biot has done everything that was possible to do in order that M. Laurent should win, and the final result is a great grief to him. But really,” the younger man added, more indulgent than the old man, and divided between his wishes for Laurent and the fear of the sorrow Balard would have felt, “M. Balard would not have deserved so much misfortune. Think of the disgrace it would have been to him if there had been a second vote favourable to Laurent, especially coming from the Institute of which he is a member.” At the end of that campaign, Biot in a fit of misanthropy which excepted Pasteur alone, and knowing that Pasteur had spoken with effusion of their mutual feelings, wrote to him as follows: “I am touched by your acknowledgment of my deep and sincere affection for you, and I thank you for it. But whilst keeping your attachment for me as I preserve mine for you, let me for the future rejoice in it in the secret recesses of my heart and of yours. The world is jealous of friendships however disinterested, and my affection for you is such that I wish people to feel that they honour themselves by appreciating you, rather than that they should know that you love me and that I love you. Farewell. Persevere in your good feelings as in your splendid career, and be happy. Your friend.”

The character of Biot, a puzzle to Sainte Beuve, seems easier to understand after reading those letters, written in a small conscientious hand. The great critic wrote: “Who will give us the secret key to Biot’s complex nature, to the curiosities, aptitudes, envies, prejudices, sympathies, antipathies, folds and creases of every kind in his character?” Even with no other documents, the history of his relations with Pasteur would throw light upon this nature, not so “complex” after all. From the day when Pasteur worked out his first experiment before Biot, at first suspicious, then astonished and finally touched to the heart, until the period of absolute mutual confidence and friendship, we see rising before us the image of this true scientist, with his rare independence, his good-will towards laborious men and his mercilessness to every man who, loving not Science for its own sake, looked upon a discovery as a road to fortune, pecuniary or political.

He loved both science and letters, and, now that age had bent his tall form, instead of becoming absorbed in his own recollections and the contemplation of his own labours, he kept his mind open, happy to learn more every day and to anticipate the future of Pasteur.

During the vacation of 1851 Pasteur came to Paris to bring Biot the results of new researches on aspartic and malic acids, and he desired his father to join him in order to efface the sad impression left by his former journey in 1838. Biot and his wife welcomed the father and son as they would have welcomed very few friends. Touched by so much kindness, Joseph Pasteur on his return in June wrote Biot a letter full of gratitude, venturing at the same time to send the only thing it was in his power to offer, a basket of fruit from his garden. Biot answered as follows: “Sir, my wife and I very much appreciate the kind expressions in the letter you have done me the honour of writing me. Our welcome to you was indeed as hearty as it was sincere, for I assure you that we could not see without the deepest interest such a good and honourable father sitting at our modest table with so good and distinguished a son. I have never had occasion to show that excellent young man any feelings but those of esteem founded on his merit, and an affection inspired by his personality. It is the greatest pleasure that I can experience in my old age, to see young men of talent working industriously and trying to progress in a scientific career by means of steady and persevering labour, and not by wretched intriguing. That is what has made your son dear to me, and his affection for me adds yet to his other claims and increases that which I feel for him. We are therefore even with one another. As to your kindness in wishing that I should taste fruit from your garden, I am very grateful for it, and I accept it as cordially as you send it.”

Pasteur had also brought Biot some other products—a case full of new crystals. Starting from the external configuration of crystals, he penetrated the individual constitution of their molecular groups, and from this point of departure, he then had recourse to the resources of chemistry and optics. Biot never ceased to admire the sagacity of the young experimentalist who had turned what had until then been a mere crystallographic character into an element of chemical research.

Equally interested by the general consequences of these studies, so delicate and so precise, M. de Senarmont wished in his turn to examine the crystals. No one approved more fully than he the expressions of the old scientist, who ended in this way his 1851 report: “If M. Pasteur persists in the road he has opened, it may be predicted of him that what he has found is nothing to what he will find.” And, delighted to see the important position that Pasteur was taking at Strasburg and the unexpected extension of crystallography, Biot wrote to him: “I have read with much interest the thesis of your brother-in-law, M. Loir. It is well conceived and well written, and he establishes with clearness many very curious facts. M. de Senarmont has also read it with very great pleasure, and I beg you will transmit our united congratulations to your brother-in-law.” Biot added, mixing as he was wont family details with scientific ideas: “We highly appreciated your father, the rectitude of his judgment, his firm, calm, simple reason and the enlightened love he bears you.”

“My plan of study is traced for this coming year,” wrote Pasteur to Chappuis at the end of December. “I am hoping to develop it shortly in the most successful manner.... I think I have already told you that I am on the verge of mysteries, and that the veil which covers them is getting thinner and thinner. The nights seem to me too long, yet I do not complain, for I prepare my lectures easily, and often have five whole days a week that I can give up to the laboratory. I am often scolded by Mme. Pasteur, but I console her by telling her that I shall lead her to fame.”

He already foresaw the greatness of his work. However he dare not speak of it, and kept his secret, save with the confidante who was now a collaborator, ever ready to act as secretary, watching over the precious health of which he himself took no account, an admirable helpmeet, to whom might be applied the Roman definition, socia rei humanæ atque divinæ. Never did life shower more affection upon a man. Everything at that time smiled upon him. Two fair children in the home, great security in his work, no enemies, and the comfort of receiving the approval and counsel of masters who inspired him with a feeling of veneration.

“At my age,” wrote Biot to Pasteur, “one lives only in the interest one takes in those one loves. You are one of the small number who can provide such food for my mind.” And alluding in that same letter (December 22, 1851) to four reports successively approved of by Balard, Dumas, Regnault, Chevreul, Senarmont and Thenard: “I was very happy to see, in those successive announcements of ideas of so new and so far-reaching a nature, that you have said—and that we have made you say—nothing that should now be contradicted or objected to in one single point. I still have in my hands the pages of your last paper concerning the optical study of malic acid. I have not yet returned them to you, as I wish to extract from them some results that I shall place to your credit in a paper I am now writing.”

It was no longer Biot and Senarmont only who were watching the growing importance of Pasteur’s work. At the beginning of the year 1852 the physicist Regnault thought of making Pasteur a corresponding member of the Institute. Pasteur was still under thirty. There was a vacancy in the General Physics section, why not offer it to him? said Regnault, with his usual kindliness. Biot shook his head: “It is to the Chemistry section that he ought to belong.” And, with the courage of sincere affection, he wrote to Pasteur, “Your work marks your place in chemistry rather than physics, for in chemistry you are in the front rank of inventors, whilst in physics you have applied processes already known rather than invented new ones. Do not listen to people, who, without knowing the ground, would cause you to desire, and even to hastily obtain, a distinction which would be above your real and recognized claims.... Besides, you can see for yourself how much your work of the last four years has raised you in every one’s estimation. And that place, which you have made for yourself in the general esteem, has the advantage of not being subject to the fluctuations of the ballot. Farewell, dear friend, write to me when you have time, and be assured that my interest in hard workers is about the only thing which yet makes me wish to live. Your friend.”

Pasteur gratefully accepted these wise counsels. In an excess of modesty, he wrote to Dumas that he should not apply as candidate even if a place for a correspondent were vacant in the Chemistry section. “Do you then believe,” answered Dumas with a vivacity very unlike his usual solemn calmness, “do you believe that we are insensible to the glory which your work reflects on French chemistry, and on the Ecole from whence you come? The very day I entered the Ministry, I asked for the Cross[22] for you. I should have had in giving it to you myself a satisfaction which you cannot conceive. I don’t know whence the delay and difficulty arise. But what I do know is that you make my blood boil when you speak in your letter of the necessity of leaving a free place in chemistry to the men you mention, one or two excepted.... What opinion have you then of our judgment? When there is a vacant place, you shall be presented, supported and elected. It is a question of justice and of the great interests of science: we shall make them prevail.... When the day comes, there will be means found to do what is required for the interests of science, of which you are one of the firmest pillars, and one of the most glorious hopes. Heartily yours.”

“My dear father,” wrote Pasteur, sending his father a copy of this letter, “I hope you will be proud of M. Dumas’ letter. It surprised me very much. I did not believe that my work deserved such a splendid testimony, though I recognize its great importance.”

Thus were associated in Pasteur the full consciousness of his great mental power with an extreme ingenuousness. Instead of the pride and egotism provoked, almost excusably, in so many superior men by excessive strength, his character presented the noblest delicacy.

Another arrangement occurred to Regnault: that he himself should accept the direction of the Sèvres Manufactory, and give up to Pasteur his professorship at the Ecole Polytechnique. Others suggested that Pasteur should become chief lecturer at the Ecole Normale. Rumours of these possibilities reached Strasburg, but Pasteur’s thoughts were otherwise absorbed. He was concerned with the manner in which he could modify the crystalline forms of certain substances which, though optically active, did not at the first view present the hemihedral character, and with the possibility of provoking the significant faces by varying the nature of the dissolving agents. Biot was anxious that he should not be disturbed in these ingenious researches, and advised him to remain at Strasburg in terms as vigorous as any of his previous advice. “As to the accidents which come from or depend on men’s caprice, be strong-minded enough to disdain them yet awhile. Do not trouble about anything, but pursue indefatigably your great career. You will be rewarded in the end, the more certainly and unquestionably that you will have deserved it more fully. The time is not far when those who can serve you efficiently will feel as much pride in doing so as shame and embarrassment in not having done so already.”

When Pasteur came to Paris in August, for what he might have called his annual pilgrimage, Biot had reserved for him a most agreeable surprise. Mitscherlich was in Paris, where he had come, accompanied by another German crystallographer, G. Rose, to thank the Académie for appointing him a foreign Associate. They both expressed a desire to see Pasteur, who was staying in a hotel in the Rue de Tournon. Biot, starting for his daily walk round the Luxembourg Garden, left this note: “Please come to my house to-morrow at 8 a.m., if possible with your products. M. Mitscherlich and M. Rose are coming at 9 to see them.” The interview was lengthy and cordial. In a letter to his father—who now knew a great deal about crystals and their forms, thanks to Pasteur’s lucid explanations—we find these words. “I spent two and a half hours with them on Sunday at the Collège de France, showing them my crystals. They were much pleased, and highly praised my work. I dined with them on Tuesday at M. Thenard’s; you will like to see the names of the guests: Messrs. Mitscherlich, Rose, Dumas, Chevreul, Regnault, Pelouze, Péligot, C. Prévost, and Bussy. You see I was the only outsider, they are all members of the Académie.... But the chief advantage of my meeting these gentlemen is that I have heard from them the important fact that there is a manufacturer in Germany who again produces some racemic acid. I intend to go and see him and his products, so as to study thoroughly that singular substance.”

At the time when scientific novels were in fashion, a whole chapter might have been written on Pasteur in search of that acid. In order to understand in a measure his emotion on learning that a manufacturer in Saxony possessed this mysterious acid, we must remember that the racemic acid—produced for the first time by Kestner at Thann in 1820, through a mere accident in the manufacture of tartaric acid—had suddenly ceased to appear, in spite of all efforts to obtain it again. What then was the origin of it?

Mitscherlich believed that the tartars employed by this Saxony manufacturer came from Trieste. “I shall go to Trieste,” said Pasteur; “I shall go to the end of the world. I must discover the source of racemic acid, I must follow up the tartars to their origin.” Was the acid existent in crude tartars, such as Kestner received in 1820 from Naples, Sicily, or Oporto? This was all the more probable from the fact that from the day when Kestner began to use semi-refined tartars he had no longer found any racemic acid. Should one conclude that it remained stored up in the mother-liquor?

With a feverish impetuosity that nothing could soothe, Pasteur begged Biot and Dumas to obtain for him a mission from the Ministry or the Académie. Exasperated by red tape delays, he was on the point of writing directly to the President of the Republic. “It is a question,” he said, “that France should make it a point of honour to solve through one of her children.” Biot endeavoured to moderate this excessive impatience. “It is not necessary to set the Government in motion for this,” he said, a little quizzically. “The Academy, when informed of your motives might very well contribute a few thousand francs towards researches on the racemic acid.” But when Mitscherlich gave Pasteur a letter of recommendation to the Saxony manufacturer, whose name was Fikentscher and who lived near Leipzig, Pasteur could contain himself no longer, and went off, waiting for nothing and listening to no one. His travelling impressions were of a peculiar nature. We will extract passages from a sort of diary addressed to Madame Pasteur so that she might share the emotions of this pursuit. He starts his campaign on the 12th September. “I do not stop at Leipzig, but go on to Zwischau, and then to M. Fikentscher. I leave him at nightfall and go back to him the next morning very early. I have spent all to-day, Sunday, with him. M. Fikentscher is a very clever man, and he has shown me his whole manufactory in every detail, keeping no secrets from me.... His factory is most prosperous. It comprises a group of houses which, from a distance, and situated on a height as they are, look almost like a little village. It is surrounded by 20 hectares[23] of well cultivated ground. All this is the result of a few years’ work. As to the question, here is a little information that you will keep strictly to yourself for the present. M. Fikentscher obtained racemic acid for the first time about twenty-two years ago. He prepared at that time rather a large quantity. Since then only a very small amount has been formed in the process of manufacture and he has not troubled to preserve it. When he used to obtain most, his tartars came from Trieste. This confirms, though not in every point, what I heard from M. Mitscherlich. Anyhow, here is my plan: Having no laboratory at Zwischau, I have just returned to Leipzig with two kinds of tartars that M. Fikentscher now uses, some of which come from Austria, and some from Italy. M. Fikentscher has assured me that I should be very well received here by divers professors, who know my name very well, he says. To-morrow Monday morning, I will go to the Université and set up in some laboratory or other. I think that in five or six days I shall have finished my examination of these tartars. Then I shall start for Vienna, where I shall stay two or three days and rapidly study Hungarian tartars.... Finally I shall go to Trieste, where I shall find tartars of divers countries, notably those of the Levant, and those of the neighbourhood of Trieste itself. On arriving here at M. Fikentscher’s I have unfortunately discovered a very regrettable circumstance. It is that the tartars he uses have already been through one process in the country from which they are exported, and this process is such that it evidently eliminates and loses the greater part of the racemic acid. At least I think so. I must therefore go to the place itself. If I had enough money I should go on to Italy; but that is impossible, it will be for next year. I shall give ten years to it if necessary; but it will not be, and I am sure that in my very next letter I shall be able to tell you that I have some good results. For instance, I am almost sure to find a prompt means of testing tartars from the point of view of racemic acid. That is a point of primary importance for my work. I want to go quickly through examining all these different tartars; that will be my first study.... M. Fikentscher will take nothing for his products. It is true that I have given him hints and some of my own enthusiasm. He wants to prepare for commercial purposes some left tartaric acid, and I have given him all the necessary crystallographic indications. I have no doubt he will succeed.”

Leipzig, Wednesday, September 15, 1852. “My dear Marie, I do not want to wait until I have the results of my researches before writing to you again. And yet I have nothing to tell you, for I have not left the laboratory for three days, and I know nothing of Leipzig but the street which goes from the Hôtel de Bavière to the Université. I come home at dusk, dine, and go to bed. I have only received, in M. Erdmann’s study, the visit of Professor Hankel, professor of physics of the Leipzig Université, who has translated all my treatises in a German paper edited by M. Erdmann. He has also studied hemihedral crystals, and I enjoyed talking with him. I shall also soon meet the professor of mineralogy, M. Naumann.

“To-morrow only shall I have a first result concerning racemic acid. I shall stay about ten days longer in Leipzig. It is more than I told you, and the reason lies in rather a happy circumstance. M. Fikentscher has kindly written to me and to a firm in Leipzig, and I heard yesterday from the head of that firm that, very likely, they can get me to-morrow some tartars absolutely crude and of the same origin as M. Fikentscher’s. The same gentleman has given me some information about a factory at Venice, and will give me a letter of recommendation to a firm in that city, also for Trieste. In this way the journey I proposed to make in that town will not simply be a pleasure trip.... I shall write to M. Biot as soon as I have important results. To-day has been a good day, and in about three or four more you will no doubt receive a satisfactory letter.”

Leipzig, September 18, 1852. “My dear Marie, the very question which has brought me here is surrounded with very great difficulties.... I have only studied one tartar thoroughly since I have been here; it comes from Naples and has been refined once. It contains racemic acid, but in such infinitesimal proportions that it can only be detected by the most delicate process. It is only by manufacture on a very large scale that a certain quantity could be prepared. But I must tell you that the first operation undergone by this tartar must have deprived it almost entirely of racemic acid. Fortunately M. Fikentscher is a most enlightened man, he perfectly understands the importance of this acid and he is prepared to follow most minutely the indications that I shall give him in order to obtain this singular substance in quantities such that it can again be easily turned into commercial use. I can already conceive the history of this product. M. Kestner must have had at his disposal in 1820 some Neapolitan tartars, as indeed he said he had, and he must have operated on crude tartar. That is the whole secret.... But is it certain that almost the whole of the acid is lost in the first manufacture undergone by tartar? I believe it is. But it must be proved. There are at Trieste and at Venice two tartar refineries of which I have the addresses. I also have letters of introduction. I shall examine there (if I find a laboratory) the residual products, and I shall make minute inquiries respecting the places the tartars used in those two cities come from. Finally, I shall procure a few kilogrammes, which I shall carefully study when I get back to France....”

Freiberg, September 23, 1852. “I arrived on the evening of the 21st at Dresden, and I had to wait until eleven the next morning to have my passport visé, so I could not start for Freiberg before seven p.m. I took advantage of that day to visit the capital of Saxony, and I can assure you that I saw some admirable things. There is a most beautiful museum containing pictures by the first masters of every school. I spent over four hours in the galleries, noting on my catalogue the pictures I most enjoyed. Those I liked I marked with a cross; but I soon put two, three crosses, according to the degree of my enthusiasm. I even went as far as four.

“I also visited what they call the green vault room, an absolutely unique collection of works of art, gems, jewels ... then some churches, avenues, admirable bridges across the Elbe....

“I then started for Freiberg at 7.... My love of crystals took me first to the learned Professor of mineralogy, Breithaupt, who received me as one would not be received in France. After a short colloquy, he passed into the next room, came back in a black tail-coat with three little decorations in his button hole, and told me he would first present me to the Baron von Beust, Superintendent of Factories, so as to obtain a permit to visit the latter.... Then he took me for a walk, talking crystals the whole time....”

P.S.—“Mind you tell M. Biot how I was received; it will please him.”

Vienna, September 27, 1852. “Yesterday, Monday morning, I set out to call upon several people. Unfortunately, I hear that Professor Schrotten is at Wiesbaden, at a scientific congress, as well as M. Seybel, a manufacturer of tartaric acid. M. Miller, a merchant for whom I had a letter of recommendation, was kind enough to ask M. Seybel’s business manager for permission for me to visit the factory in his absence. He refused, saying he was not authorized. But I did not give in; I asked for the addresses of Viennese professors, and I fortunately came upon that of a very well known scientific man, M. Redtenbacher, who has been kind to me beyond all description. At 6 a.m. he came to my hotel, and we took the train at 7 for the Seybel manufactory, which is at a little distance from Vienna. We were received by the chemist of the factory, who made not the slightest difficulty in introducing us into the sanctuary, and after many questions we ended by being convinced that the famous racemic acid was seen there last winter.... I reserve for later many details of great interest, for here they have operated for years on crude tartar. I came away very happy.

“There is another factory of tartaric acid in Vienna. We go there; I repeat through M. Redtenbacher my string of questions. They have seen nothing. I ask to see their products, and I come upon a barrel full of tartaric acid crystals, on the surface of which I think I perceive the substance. A first test made with dirty old glasses then and there confirms my doubts; they become a certainty a few moments later at M. Redtenbacher’s laboratory. We dine together; then we go back to the factory, where we learn, miraculous to relate, that they are just now embarrassed in their manufacturing process, and, almost certainly, the product which hinders them—though it is in a very small quantity, and they take it for sulphate of potash—is no other than racemic acid. I wish I could give you more details of this eventful day. I was to have left Vienna to-day, but, as you will understand, I shall stay until I have unravelled this question. I have already in the laboratory three kinds of products from the factory. To-morrow night, or the day after, I shall know what to think....

“You remember what I used to say to you and to M. Dumas, that almost certainly the first operation which tartar goes through in certain factories causes it to lose all or nearly all its racemic acid. Well, in the two Viennese factories, it is only two years since they began to operate on crude tartar, and it is only two years since they first saw the supposed sulphate of potash, the supposed sulphate of magnesia. For, at M. Seybel’s, they had taken for sulphate of magnesia the little crystals of racemic acid.

“Shortly, this is as far as I have come—I spare you many details:—

1. “The Naples tartar contains racemic acid.

2. “The Austrian tartar (neighbourhood of Vienna) contains racemic acid.

3. “The tartars of Hungary, Croatia, Carniola contain racemic acid.

4. “The tartar of Naples contains notably more than the latter, for it presents racemic acid even after one refining process, whilst that from Austria and Hungary only presents it when in the crude state.

“I believe it now to be extremely probable that I shall find some racemic acid in French tartars, but in very small quantities; and if it is not detected it is because all the circumstances of the manufacture of tartaric acid are unknown or unappreciated, or because some little precaution is neglected that would preserve it or make it visible.

“You see, dear Marie, how useful was my journey.”

“Vienna, September 30, 1852. I am not going to Trieste; I shall start for Prague this evening.”

“Prague, October 1, 1852. Here is a startling piece of news. I arrive in Prague; I settle down in the Hôtel d’Angleterre, have lunch, and call on M. Rochleder, Professor of chemistry, so that he may introduce me to the manufacturer. I go to the chemist of the factory, Dr. Rassmann, for whom I had a letter from M. Redtenbacher, his former master. That letter contained all the questions that I usually make to the manufacturers of tartaric acid.

“Dr. Rassmann hardly took time to read the letter; he saw what it dealt with, and said to me: ‘I have long obtained racemic acid. The Paris Pharmaceutical Society offered a prize for whoever manufactured it. It is a product of manufacture; I obtain it with the assistance of tartaric acid.’ I took the chemist’s hand affectionately, and made him repeat what he had said. Then I added: ‘You have made one of the greatest discoveries that it is possible to make in chemistry. Perhaps you do not realise as I do the full importance of it. But allow me to tell you that, with my ideas, I look upon that discovery as impossible. I do not ask for your secret; I shall await the publication of it with the greatest impatience. So that is really true? You take a kilogramme of pure tartaric acid, and with that you make racemic acid?’

“‘Yes,’ he said; ‘but it is still’ ... and as he had some difficulty in expressing himself, I said: ‘It is still surrounded with great difficulties?’

“‘Yes, monsieur.’

“Great heavens! what a discovery! if he had really done what he says! But no; it is impossible. There is an abyss to cross, and chemistry is yet too young.”

Second letter, same date. “M. Rassmann is mistaken.... He has never obtained racemic acid with pure tartaric acid. He does what M. Fikentscher and the Viennese manufacturers do, with slight differences, which confirm the general opinion I expressed in my letter to M. Dumas a few days ago.”

That letter, and also another addressed to Biot, indicated that racemic acid was formed in varying quantities in the mother-liquor, which remained after the purification of crude tartars.

“I can at last,” Pasteur wrote from Leipzig to his wife, “turn my steps again towards France. I want it; I am very weary.”

In an account of this journey in a newspaper called La Vérité there was this sentence, which amused everybody, Pasteur included: “Never was treasure sought, never adored beauty pursued over hill and vale with greater ardour.”

But the hero of scientific adventures was not satisfied. He had foreseen by the examination of crystalline forms, the correlation between hemihedral dissymmetry and rotatory power; this was, to his mind, a happy foresight. He had afterwards succeeded in separating the racemic acid, inactive on polarized light, into two acids, left and right, endowed with equal but contrary rotatory powers; this was a discovery deservedly qualified as memorable by good judges in those matters. Now he had indicated the mother-liquor as a source of racemic acid, and this was a precious observation that Kestner, who was specially interested in the question, confirmed in a letter to the Académie des Sciences (December, 1852), sending at the same time three large phials of racemic acid, one of which, made of thin glass, broke in Biot’s hands. But a great advance, apparently unrealizable, remained yet to be accomplished. Could not racemic acid be produced by the aid of tartaric acid?

Pasteur himself, as he told the optimist Rassmann, did not believe such a transformation possible. But, by dint of ingenious patience, of trials, of efforts of all sorts, he fancied he was nearing the goal. He wrote to his father: “I am thinking of one thing only, of the hope of a brilliant discovery which seems not very far. But the result I foresee is so extraordinary that I dare not believe it.” He told Biot and Senarmont of this hope. Both seemed to doubt. “I advise you,” wrote Senarmont, “not to speak until you can say: ‘I obtain racemic acid artificially with some tartaric acid, of which I have myself verified the purity; the artificial acid, like the natural, divides itself into equal equivalents of left and right tartaric acids, and those acids have the forms, the optical properties, all the chemical properties of those obtained from the natural acid.’ Do not believe that I want to worry you; the scruples I have for you I should have for myself; it is well to be doubly sure when dealing with such a fact.” But with Biot, Senarmont was less reserved; he believed the thing done. He said so to Biot, who, prudent and cautious, still desirous of warning Pasteur, wrote to him on May 27, 1853, speaking of Senarmont: “The affection with which your work, your perseverance and your moral character have inspired him makes him desire impossible prodigies for you. My friendship for you is less hastily hopeful and harder to convince. However, enjoy his friendship fully, and be as unreserved with him as you are with me. You can do so in full security; I do not know a stronger character than his. I have said and repeated to him how happy I am to see the affection he bears you. For there will be at least one man who will love you and understand you when I am gone. Farewell; enough sermons for to-day; a man must be as I am, in his eightieth year, to write such long homilies. Fortunately you are accustomed to mine, and do not mind them.”

At last, on the first of June, here is the letter announcing the great fact: “My dear father, I have just sent out the following telegram: Monsieur Biot, Collège de France, Paris. I transform tartaric acid into racemic acid; please inform MM. Dumas and Senarmont. Here is at last that racemic acid (which I went to seek at Vienna) artificially obtained through tartaric acid. I long believed that that transformation was impossible. This discovery will have incalculable consequences.”

“I congratulate you,” answered Biot on the second of June. “Your discovery is now complete. M. de Senarmont will be as delighted as I am. Please congratulate also Mme. Pasteur from me; she must be as pleased as you.” It was by maintaining tartrate of cinchonin at a high temperature for several hours that Pasteur had succeeded in transforming tartaric acid into racemic acid. Without entering here into technical details (which are to be found in a report of the Paris Pharmaceutical Society, concerning the prize accorded to Pasteur for the artificial production of racemic acid) it may be added that he had also produced the neutral tartaric acid—that is: with no action on polarized light—which appeared at the expense of racemic acid already formed. There were henceforth four different tartaric acids:—(1) the right or dextro-tartaric acid; (2) the left or lævo-tartaric acid; (3) the combination of the right and the left or racemic acid; and (4) the meso-tartaric acid, optically inactive.

The reports of the Académie des Sciences also contain accounts of occasional discoveries, of researches of all kinds accessory to the history of racemic acid. Thus aspartic acid had caused Pasteur to make a sudden journey from Strasburg to Vendôme. A chemist named Dessaignes—who was municipal receiver of that town, and who found time through sheer love of science for researches on the constitution of divers substances—had announced a fact which Pasteur wished to verify; it turned out to be inaccurate.

One whole sitting of the Académie, the third of January, 1853, was given up to Pasteur’s name and growing achievements.

After all this Pasteur came back to Arbois with the red ribbon of the Legion of Honour. He had not won it in the same way as his father had, but he deserved it as fully. Joseph Pasteur, delighting in his illustrious son, wrote effusively to Biot; indeed the old scientist had had his share in this act of justice. Biot answered in the following letter, which is a further revelation of his high and independent ideal of a scientific career.

“Monsieur, your good heart makes out my share to be greater than it is. The splendid discoveries made by your worthy and excellent son, his devotion to science, his indefatigable perseverance, the conscientious care with which he fulfils the duties of his situation, all this had made his position such that there was no need to solicit for him what he had so long deserved. But one might boldly point out that it would be a real loss to the Order if he were not promptly included within its ranks. That is what I did, and I am very glad to see that the too long delay is now at an end. I wished for this all the more as I knew of your affectionate desire that this act of justice should be done. Allow me to add, however, that in our profession our real distinction depends on us alone, fortunately, and not on the favour or indifference of a minister. In the position that your son has acquired, his reputation will grow with his work, no other help being needed; and the esteem he already enjoys, and which will grow day by day, will be accorded to him, without gainsaying or appeal, by the Grand Jury of scientists of all nations—an absolutely just tribunal, the only one we recognize.

“Allow me to add to my congratulations the expression of the esteem and cordial affection with which you have inspired me.”

On his return to Strasburg Pasteur went to live in a house in the Rue des Couples, which suited him as being near the Académie and his laboratory; it also had a garden where his children could play. He was full of projects, and what he called the “spirit of invention” daily suggested some new undertaking. The neighbourhood of Germany, at that time a veritable hive of busy bees, was a fertile stimulant to the French Faculty at Strasburg.

But material means were lacking. When Pasteur received the prize of 1,500 francs given him by the Pharmaceutical Society, he gave up half of it to buying instruments which the Strasburg laboratory was too poor to afford. The resources then placed by the State at his disposal by way of contribution to the expenses of a chemistry class only consisted of 1,200 francs under the heading “class expenses.” Pasteur had to pay the wages of his laboratory attendant out of it. Now that he was better provided, thanks to his prize, he renewed his studies on crystals.

Taking up an octahedral crystal, he broke off a piece of it, then replaced it in its mother-liquor. Whilst the crystal was growing larger in every direction by a deposit of crystalline particles, a very active formation was taking place on the mutilated part; after a few hours the crystal had again assumed its original shape. The healing up of wounds, said Pasteur, might be compared to that physical phenomenon. Claude Bernard, much struck later on by these experiments of Pasteur’s and recalling them with much praise, said in his turn—

“These reconstituting phenomena of crystalline redintegration afford a complete comparison with those presented by living beings in the case of a wound more or less deep. In the crystal as in the animal, the damaged part heals, gradually taking back its original shape, and in both cases the reformation of tissue is far more active in that particular part than under ordinary evolutive conditions.”

Thus those two great minds saw affinities hidden under facts apparently far apart. Other similarities yet more unexpected carried Pasteur away towards the highest region of speculation. He spoke with enthusiasm of molecular dissymmetry; he saw it everywhere in the universe. These studies in dissymmetry gave birth twenty years later to a new science arising immediately out of his work, viz. stereo-chemistry, or the chemistry of space. He also saw in molecular dissymmetry the influence of a great cosmic cause—

“The universe,” he said one day, “is a dissymmetrical whole. I am inclined to think that life, as manifested to us, must be a function of the dissymmetry of the universe and of the consequences it produces. The universe is dissymmetrical; for, if the whole of the bodies which compose the solar system were placed before a glass moving with their individual movements, the image in the glass could not be superposed to the reality. Even the movement of solar life is dissymmetrical. A luminous ray never strikes in a straight line the leaf where vegetable life creates organic matter. Terrestrial magnetism, the opposition which exists between the north and south poles in a magnet, that offered us by the two electricities positive and negative, are but resultants from dissymmetrical actions and movements.”

“Life,” he said again, “is dominated by dissymmetrical actions. I can even foresee that all living species are primordially, in their structure, in their external forms, functions of cosmic dissymmetry.”

And there appeared to him to be a barrier between mineral or artificial products and products formed under the influence of life. But he did not look upon it as an impassable one, and he was careful to say, “It is a distinction of fact and not of absolute principle.” As nature elaborates immediate principles of life by means of dissymmetrical forces, he wished that the chemist should imitate nature, and that, breaking with methods founded upon the exclusive use of symmetrical forces, he should bring dissymmetrical forces to bear upon the production of chemical phenomena. He himself, after using powerful magnets to attempt to introduce a manifestation of dissymmetry into the form of crystals, had had a strong clockwork movement constructed, the object of which was to keep a plant in continual rotatory motion first in one direction then in another. He also proposed to try to keep a plant alive, from its germination under the influence of solar rays reversed by means of a mirror directed by a heliostat.

But Biot wrote to him: “I should like to be able to turn you from the attempts you wish to make on the influence of magnetism on vegetation. M. de Senarmont agrees with me. To begin with, you will spend a great deal on the purchase of instruments with the use of which you are not familiar, and of which the success is very doubtful. They will take you away from the fruitful course of experimental researches which you have followed hitherto, where there is yet so much for you to do, and will lead you from the certain to the uncertain.”

“Louis is rather too preoccupied with his experiments,” wrote Mme. Pasteur to her father-in-law; “you know that those he is undertaking this year will give us, if they succeed, a Newton or a Galileo.”

But success did not come. “My studies are going rather badly,” wrote Pasteur in his turn (December 30). “I am almost afraid of failing in all my endeavours this year, and of having no important achievement to record by the end of next year. I am still hoping, though I suppose it was rather mad to undertake what I have undertaken.”

Whilst he was thus struggling, an experiment, which for others would have been a mere chemical curiosity, interested him passionately. Recalling one day how his first researches had led him to the study of ferments: “If I place,” he said, “one of the salts of racemic acid, paratartrate or racemate of ammonia, for instance, in the ordinary conditions of fermentation, the dextro-tartaric acid alone ferments, the other remains in the liquor. I may say, in passing, that this is the best means of preparing lævo-tartaric acid. Why does the dextro-tartaric acid alone become putrefied? Because the ferments of that fermentation feed more easily on the right than on the left molecules.”

“I have done yet more,” he said much later, in a last lecture to the Chemical Society of Paris; “I have kept alive some little seeds of penicillium glaucum—that mucor which is to be found everywhere—on the surface of ashes and paratartaric acid and I have seen the lævo-tartaric acid appear....”

What seemed to him startling in those two experiments was to find molecular dissymmetry appear as a modifying agent on chemical affinities in a phenomenon of the physiological order.

By an interesting coincidence it was at the very moment when his studies were bringing him towards fermentations that he was called to a country where the local industry was to be the strongest stimulant to his new researches.

CHAPTER IV
1855—1859

In September, 1854, he was made Professor and Dean of the new Faculté des Sciences at Lille. “I need not, Sir,” wrote the Minister of Public Instruction, M. Fortoul, in a letter where private feelings were mixed with official solemnity, “recall to your mind the importance which is attached to the success of this new Faculty of Science, situated in a town which is the richest centre of industrial activity in the north of France. By giving you the direction of it, I show the entire confidence which I have placed in you. I am convinced that you will fulfil the hopes which I have founded upon your zeal.”

Built at the expense of the town, the Faculté was situated in the Rue des Fleurs. In the opening speech which he pronounced on December 7, 1854, the young Dean expressed his enthusiasm for the Imperial decree of August 22, which brought two happy innovations into the Faculties of Science: (1) The pupils might, for a small annual sum, enter the laboratory and practise the principal experiments carried out before them at the classes; and (2) a new diploma was created. After two years of practical and theoretical study the young men who wished to enter an industrial career could obtain this special diploma and be chosen as foremen or overseers. Pasteur was overjoyed at being able to do useful work in that country of distilleries, and to attract large audiences to the new Faculty. “Where in your families will you find,” he said, to excite indolent minds—“where will you find a young man whose curiosity and interest will not immediately be awakened when you put into his hands a potato, when with that potato he may produce sugar, with that sugar alcohol, with that alcohol æther and vinegar? Where is he that will not be happy to tell his family in the evening that he has just been working out an electric telegraph? And, gentlemen, be convinced of this, such studies are seldom if ever forgotten. It is somewhat as if geography were to be taught by travelling; such geography is remembered because one has seen the places. In the same way your sons will not forget what the air we breathe contains when they have once analysed it, when in their hands and under their eyes the admirable properties of its elements have been resolved.”

After stating his wish to be directly useful to these sons of manufacturers and to put his laboratory at their disposal, he eloquently upheld the rights of theory in teaching—

“Without theory, practice is but routine born of habit. Theory alone can bring forth and develop the spirit of invention. It is to you specially that it will belong not to share the opinion of those narrow minds who disdain everything in science which has not an immediate application. You know Franklin’s charming saying? He was witnessing the first demonstration of a purely scientific discovery, and people round him said: ‘But what is the use of it?’ Franklin answered them: ‘What is the use of a new-born child?’ Yes, gentlemen, what is the use of a new-born child? And yet, perhaps, at that tender age, germs already existed in you of the talents which distinguish you! In your baby boys, fragile beings as they are, there are incipient magistrates, scientists, heroes as valiant as those who are now covering themselves with glory under the walls of Sebastopol. And thus, gentlemen, a theoretical discovery has but the merit of its existence: it awakens hope, and that is all. But let it be cultivated, let it grow, and you will see what it will become.

“Do you know when it first saw the light, this electric telegraph, one of the most marvellous applications of modern science? It was in that memorable year, 1822: Oersted, a Danish physicist, held in his hands a piece of copper wire, joined by its extremities to the two poles of a Volta pile. On his table was a magnetized needle on its pivot, and he suddenly saw (by chance you will say, but chance only favours the mind which is prepared) the needle move and take up a position quite different from the one assigned to it by terrestrial magnetism. A wire carrying an electric current deviates a magnetized needle from its position. That, gentlemen, was the birth of the modern telegraph. Franklin’s interlocutor might well have said when the needle moved: ‘But what is the use of that?’ And yet that discovery was barely twenty years old when it produced by its application the almost supernatural effects of the electric telegraph!”

The small theatre where Pasteur gave his chemistry lessons soon became celebrated in the students’ world.

The faults had disappeared with which Pasteur used to reproach himself when he first taught at Dijon and later at Strasburg. He was sure of himself, he was clear in his explanations; the chain of thought, the fitness of words, all was perfect. He made few experiments, but those were decisive. He endeavoured to bring out every observation or comparison they might suggest. The pupil who went away delighted from the class did not suspect the care each of those apparently easy lessons had cost. When Pasteur had carefully prepared all his notes, he used to make a summary of them; he had these summaries bound together afterwards. We may thus sketch the outline of his work; but who will paint the gesture of demonstration, the movement, the grave penetrating voice, the life in short?

After a few months the Minister wrote to M. Guillemin, the rector, that he was much pleased with the success of this Faculty of Sciences at Lille, “which already owes it to the merit of the teaching—solid and brilliant at the same time—of that clever Professor, that it is able to rival the most flourishing Faculties.” The Minister felt he must add some official advice: “But M. Pasteur must guard against being carried away by his love for science, and he must not forget that the teaching of the Faculties, whilst keeping up with scientific theory, should, in order to produce useful and far-reaching results, appropriate to itself the special applications suitable to the real wants of the surrounding country.”

A year after the inauguration of the new Faculty, Pasteur wrote to Chappuis: “Our classes are very well attended; I have 250 to 300 people at my most popular lectures, and we have twenty-one pupils entered for laboratory experiments. I believe that this year, like last year, Lille holds the first rank for that innovation, for I am told that at Lyons there were but eight entries.” It was indeed a success to distance Lyons. “The zeal of all is a pleasure to watch (January, 1856). It reaches that point that four of the professors take the trouble to have their manuscript lessons printed; there are already 120 subscribers for the course of applied mechanics.

“Our building is fortunately completed; it is large and handsome, but will soon become insufficient owing to the progress of practical teaching.

“We are very comfortably settled on the first floor, and I have (on the ground floor immediately below) what I have always wished for, a laboratory where I can go at any time. This week, for instance, the gas remains on, and operations follow their course whilst I am in bed. In this way I try to make up a little of the time which I have to give to the direction of all the rather numerous departments in our Faculties. Add to this that I am a member of two very active societies, and that I have been entrusted, at the suggestion of the Conseil-Général,[24] with the testing of manures for the département of the Nord, a considerable work in this rich agricultural land, but one which I have accepted eagerly, so as to popularize and enlarge the influence of our young Faculty.

“Do not fear lest all this should keep me from the studies I love. I shall not give them up, and I trust that what is already accomplished will grow without my help, with the growth that time gives to everything that has within it the germ of life. Let us all work; that only is enjoyable. I am quoting M. Biot, who certainly is an authority on that subject. You saw the share he took the other day in a great discussion at the Académie des Sciences; his presence of mind, high reasoning powers, and youthfulness were magnificent, and he is eighty-four!”

In a mere study on Pasteur as a scientific man, the way in which he understood his duties as Dean would only be a secondary detail. It is not so here, the very object of this book being to paint what he was in all the circumstances, all the trials of life. Besides his professional obligations, his kindness in leaving his laboratory, however hard the sacrifice, bears witness to an ever present devotion. For instance, he took his pupils round factories and foundries at Aniche, Denain, Valenciennes, St. Omer. In July, 1856, he organized for the same pupils a tour in Belgium. He took them to visit factories, iron foundries, steel and metal works, questioning the foremen with his insatiable curiosity, pleased to induce in his tall students a desire to learn. All returned from these trips with more pleasure in their work; some with the fiery enthusiasm that Pasteur wished to see.

The sentence in his Lille speech, “in the fields of observation, chance only favours the mind which is prepared,” was particularly applicable to him. In the summer of 1856 a Lille manufacturer, M. Bigo, had, like many others that same year, met with great disappointments in the manufacture of beetroot alcohol. He came to the young Dean for advice. The prospect of doing a kindness, of communicating the results of his observations to the numerous hearers who crowded the small theatre of the Faculty, and of closely studying the phenomena of fermentation which preoccupied him to such a degree, caused Pasteur to consent to make some experiments. He spent some time almost daily at the factory. On his return to his laboratory—where he only had a student’s microscope and a most primitive coke-fed stove—he examined the globules in the fermentation juice, he compared filtered with non-filtered beetroot juice, and conceived stimulating hypotheses often to be abandoned in face of a fact in contradiction with them. Above some note made a few days previously, where a suggested hypothesis had not been verified by fact, he would write: “error,” “erroneous,” for he was implacable in his criticism of himself.